Proportions and Linearity โธ 7โ8
Module 1 Rational and Irrational Numbers
2 One- and Two-Variable Equations
3 Two-Dimensional Geometry
4 Graphs of Linear Equations and Systems of Linear Equations
5 Functions and Three-Dimensional Geometry
6 Probability and Statistics
Student Edition: Grade 7โ8, Module 1, Title A Story of Ratiosยฎ
ยฉ Great Minds PBC 2 7โ8 โธ M1 EUREKA MATH2 Contents Rational and Irrational Numbers Topic A Add and Subtract Rational Numbers 5 Lesson 1 Adding Integers and Rational Numbers 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 2 KAKOOMAยฎ with Rational Numbers 29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 3 Finding Distances to Find Differences 45 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 4 Subtracting Integers 57 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 5 Subtracting Rational Numbers 67 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Topic B Multiply and Divide Rational Numbers 81 Lesson 6 Multiplying Integers and Rational Numbers 83 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 7 Exponential Expressions and Relating Multiplication to Division 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 8 Dividing Integers and Rational Numbers 115 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 9 Decimal Expansions of Rational Numbers 127 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Topic C Properties of Exponents and Scientific Notation 139 Lesson 10 Large and Small Positive Numbers 141 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 11 Products of Exponential Expressions with Positive Whole-Number Exponents 153 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 12 More Properties of Exponents 169 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 13 Making Sense of Integer Exponents 181 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 14 Writing Very Large and Very Small Numbers in Scientific Notation 193 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 15 Operations with Numbers Written in Scientific Notation 211 Lesson 16 Applications with Numbers Written in Scientific Notation 229 Lesson 17 Get to the Point 241 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Topic D Rational and Irrational Numbers 253 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 18 Solving Equations with Squares and Cubes 255 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 19 The Pythagorean Theorem 269 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 20 Using the Pythagorean Theorem 285 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 21 Approximating Values of Roots 301 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lesson 22 Rational and Irrational Numbers 311 Lesson 23 Revisiting Equations with Squares and Cubes 321
Student Edition: Grade 7โ8, Module 1, Contents
3 ยฉ Great Minds PBC EUREKA MATH2 7โ8 โธ M1 Resources Mixed Practice 1 333 . . . . . . . . . . . . . . . . . . . . . . . . . . Mixed Practice 2 337 . . . . . . . . . . . . . . . . . . . . . . . . . Fluency Resources Lesson 21 Number Lines 0 To 10 Sprint: Apply Properties of Positive and Negative Exponents 343 . . . . . . . . . . . . . 345 . . . . . . . . . . . . . . . . . . . Sprint: Addition and Subtraction of Integers 349 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sprint: Integer Multiplication and Division 353 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sprint: Scientific Notation with Positive and Negative Exponents 357 . . . . . . . . . . . . . . . . . . . Sprint: Squares 361 . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bibliography 365 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Credits 366 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Acknowledgments 367 . . . . . . . . . . . . . . . . . . . . . . .
Add and Subtract Rational Numbers
Student Edition: Grade 7โ8, Module 1, Topic A The Worst Game Show Ever
TOPIC A
T
hatโs corect! You lose $500! But... I got it right! Shouldnโt I gain money, rather than lose it?
Hm... judges
y apologies! Youโre quite right!
Thank you.
You win -$500!
This is the worst game show ever.
Itโs easy to get confused when you see something like โโ 500.โ Thatโs because the โโโ symbol has twoย meanings: โsubtractionโ and โnegative.โ
Are we dealing with the operation โsubtract 500,โ as in 150 โ 500?
Or are we dealing with the number โnegative 500,โ as in 150 + (โ500)?
Do not be deceived by words like giving or adding. Offering someone a gift of โ $500 is not a generous thing to do. In fact, it is the same as stealing $500 right out of the personโs pocket.
ยฉ Great Minds PBC 5
M ?
r m
Name Date
Adding Integers and Rational Numbers
Adding Integers
For problems 1 and 2, use the number line to model the addition expression.
1. 3 + 5
109876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 1 EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 7 LESSON 1
2. โ3 + (โ5)
109876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
For problems 3 and 4, write the addition expression that represents the situation. Then use the number line to model the addition expression and determine the sum.
3. Abdul earns $6. He then spends $2.
109876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
4. The temperature rises 2ยฐF from 0ยฐF. Then the temperature drops 6ยฐF
109876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
7โ8 โธ M1 โธ TA โธ Lesson 1 EUREKA MATH2 ยฉ Great Minds PBC 8 LESSON
5. Consider the expressions.
a. Determine the absolute values of the addends in each expression.
b. Use the number line to model each expression and determine the sum.
c. What do you notice about the distance on the number line between the first addend and the sum in each expression?
d. How can absolute value be used to help determine the sign of the sum? Write a conjecture.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 9 L ESSON
Expression Absolute Values Model Sum 5 + (โ9) 10 8 6 4 2 0 โ10 โ8 โ6 โ4 โ2 9 + (โ5) 10 8 6 4 2 0 โ10 โ8 โ6 โ4 โ2 โ5 + 9 10 8 6 4 2 0 โ10 โ8 โ6 โ4 โ2 โ9 + 5 10 8 6 4 2 0 โ10 โ8 โ6 โ4 โ2
6. Complete the table.
7. Determine the sum.
โ40 + 25 + (โ5)
7โ8 โธ M1 โธ TA โธ Lesson 1 EUREKA MATH2 ยฉ Great Minds PBC 10 LESSON
Expression
Decomposition 12
Sign of the Sum Model
+ (โ10) โ30 + 24
Adding Rational Numbers
For problems 8โ11, determine the sum.
8. 2.4 + (โ3.4)
9. 5 3 + 8 ( 3 1 8 )
10. โ3.4 + 9.8 11.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 11 LESSON
3 4
2 1 77
+
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 1
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 โธ Number Lines ยฉ Great Minds PBC 13 10 9 8 7 6 5 4 3 2 1 0 โ10 โ9 โ8 โ7 โ6 โ5 โ4 โ3 โ2 โ1
7โ8 โธ M1 โธ TA โธ Lesson 1 โธ Number Lines EUREKA MATH2 ยฉ Great Minds PBC 14 109876543210 โ10 โ9โ8โ7โ6โ5โ4โ3โ2โ1
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 โธ Number Lines ยฉ Great Minds PBC 15
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 1
For problems 1 and 2, use the number line to model the expression and determine the sum.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 17 EXIT TICKET 1 Name Date
1. โ6 + 6 10 9876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1 2. 3 + (โ7) 10 9876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
3. Consider the following expression.
โ62 + 23
a. Use the number line to model the expression.
b. Determine the sum.
7โ8 โธ M1 โธ TA โธ Lesson 1 EUREKA MATH2 ยฉ Great Minds PBC 18 EXIT TICKET
Name Date
Adding Integers and Rational Numbers
In this lesson, we
โข identified additive inverses and used a number line to model them.
โข used a number line to model addition expressions.
โข predicted the sign of the sum of addition expressions.
โข used strategies to determine sums of rational numbers.
Examples
Terminology
The additive inverse of a number is a number such that the sum of the two numbers is 0. The additive inverse of a number x is the opposite of x because x + (โx) = 0
1. Use the number line to model the expression and determine the sum.
Start where the first directed line segment ends: 8. Because the second addend is โ13, draw the directed line segment to the left and make it 13 units long.
8 + (โ13)
Start at 0. Because the first addend is 8, draw the directed line segment to the right and make it 8 units long.
The endpoint of the second directed line segment is the value of the sum. In this case, the sum is โ5.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 19 RECAP 1
10 โ10 โ5 โ6 โ7 โ8 โ9 โ4 โ3 โ2 โ1 012345 6 7 8 9
8 + (โ13) = โ5
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 1
2. Last month, Ethan withdrew $53 from his savings account. This month, he withdrew another $40.
a. Write an addition expression to represent the changes in the balance of Ethanโs savings account.
โ53 + (โ40)
Withdrawing money means taking money out of an account, so the amounts Ethan withdrew are represented by negative numbers in the expression.
b. Use the number line to model your addition expression.
Use a blank number line to draw a model that represents the addition expression. Mark the location of 0 and have the lengths of the directed line segments relate to the absolute value of the numbers they represent.
For problems 3โ5, predict whether the sum of the expression is a positive number, 0, or a negative number. Explain your reasoning.
3. โ15.3 + (โ5.4)
The sum is a negative number because both addends are negative.
4. 11 3 7 + ( 5 1 7 )
The sum is a positive number because the absolute value of 11 3 7 is greater than the absolute value of โ5 1 7 .
When the addends have the same sign, the sum also has that sign.
When two addends have opposite signs, the sum has the same sign as the addend with the greater absolute value.
7โ8 โธ M1 โธ TA โธ Lesson 1 EUREKA MATH2 ยฉ Great Minds PBC 20 RECAP
53 40 0 โ53 โ93
5. 7 8 + ( 7 8 )
The sum is 0 because 7 8 and 7 8 are additive inverses. For problems 6 and 7, determine the sum.
7. โ5.2 + (โ4.5)
When the addends are opposite values, they sum to 0.
โ5.2 + (โ4.5) = โ5 + (โ0.2) + (โ4) + (โ0.5)
= (โ5 + (โ4)) + (โ0.2 + (โ0.5))
= โ9 + (โ0.7)
= โ9.7
The two addends have opposite signs, so using decomposition and additive inverses is an effective strategy. To find
The two addends have the same sign, so decomposing the addends into integer and non-integer parts is an effective strategy to determine the sum.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 21 RECAP
6. 2 7 8 + 1 1 8 2 7 8 + 1 1 8 = 1 6 8 + ( 1 1 8 ) + 1 1 8
the additive inverse of
8 decompose โ2 7 8 into โ1 6 8 and โ1 1 8 = 1 6 8 + ( 1 1 8 + 1 1 8 ) = 1 6 8 + 0 = 1 6 8
1 1 ,
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 1
Name Date
1. Sara gains 10 points.
a. Describe an opposite action.
b. Write an addition expression that represents both actions.
c. Use the number line to model the addition expression you created in part (b). Then determine the sum.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 23
PRACTICE 1
10 9 8 7 6 5 4 3 2 1 0 โ10 โ9 โ8 โ7 โ6 โ5 โ4 โ3 โ2 โ1
2. On Monday, the temperature in Chicago was 0ยฐF at 1:00 a.m. The temperature decreased 7ยฐF. Then the temperature increased 10ยฐF
a. Write an addition expression to represent the changes in temperature.
b. Use the number line to represent the addition expression you created in part (a).
c. What is the temperature after these temperature changes?
3. What is the additive inverse of โ4.3? Explain how you know.
4. Predict whether the sum of each expression is a positive number, zero, or a negative number.
7โ8 โธ M1 โธ TA โธ Lesson 1 EUREKA MATH2 ยฉ Great Minds PBC 24 PRACTICE
โ10 โ9โ2 โ1โ4 โ3โ8 โ7 โ6 โ5106 7 8 943052 1
Expression Positive Zero Negative โ13 + 14 6 + (โ17) โ2.4 + (โ0.7) 14 9 + (โ 14 9 ) โ25.4 + 6.2 6 1 _ 3 + (โ3 2 _ 3 )
For problems 5โ7, use the number line to model the expression and determine the sum.
5. 3 + (โ6)
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 25 PRACTICE
109876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
6. โ6 + (โ3)
109876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
7. โ6 + 3
109876543210โ10โ9โ8โ7โ6โ5โ4โ3โ2โ1
8. Consider the following addition expression.
โ73 + 18
a. Use the number line to model the expression.
b. Determine the sum.
For problems 9โ12, determine the sum.
+ 35
Remember
For problems 13โ16, add.
7โ8 โธ M1 โธ TA โธ Lesson 1 EUREKA MATH2 ยฉ Great Minds PBC 26 PRACTICE
9. โ60
(โ15)
10. โ4.6 + (โ2.7) 11. 4 1 2 + (โ3 1 2 ) 12. โ8 1 9 + 12 5 9
+
13. 1 3 + 4 3 14. 5 8 + 2 8 15. 1 9 + 7 9 16. 1 10 + 14 10
17. If 4 people share 9 cups of popcorn equally, how many cups of popcorn does each person get?
18. Use each location to plot its corresponding point on the number line.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 1 ยฉ Great Minds PBC 27 PRACTICE
Location Point 3 A the opposite of 3 B โ1.5 C the opposite of โ1.5 D 3 4 E the opposite of 3 4 F 54321154320-----
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 2
Name Date
KAKOOMAยฎ with Rational Numbers
Estimate and Evaluate
For problems 1โ5, estimate, and then find the sum.
1. โ3.45 + (โ1.52)
LESSON
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 29
2
2. โ13 1 4 + 8 5 8 3. โ6 1 2 + (โ1 1 3 )
4. โ9.35 + 9.75
5. 7.63 + (โ10.42)
6. Vic has $52.13 in his checking account. At midnight, a debit of $3.06 and a debit of $18.24 will post to his account.
a. Write an addition expression to represent the situation. Then estimate the sum.
b. What is the value of the expression in part (a)?
c. What is the amount of money in Vicโs checking account after the debits post?
7โ8 โธ M1 โธ TA โธ Lesson 2 EUREKA MATH2 ยฉ Great Minds PBC 30 LESSON
Solving a KAKOOMAยฎ
7. In each four-number square, find the one number that is the sum of two other given numbers. Transfer all four sums to the puzzle below to create one final puzzle, and then solve.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 31 LESSON
ยฉ Greg Tang
1 4 โ4โ1 3 โ3.2 โ3 3.6 0.4โ0.8 5.1 โ7.2 6.8โ2.1 โ1 1 2 โ3 4 2โ1 2 6โ5 6 b ac d 1st Sum Find the number that is the sum of 2 others.
Final
Answer
Creating a KAKOOMAยฎ
8. Create your own KAKOOMAยฎ puzzle by using the blank puzzle shown. Refer to problem 7, and make sure that your KAKOOMAยฎ puzzle follows this structure. Use rational numbers between โ10 and 10. Each four-number square must include at least two non-integer rational numbers and at least one number less than 0. The same number cannot be used more than once in a square.
Find the number that is the sum of 2 others.
7โ8 โธ M1 โธ TA โธ Lesson 2 EUREKA MATH2 ยฉ Great Minds PBC 32 LESSON
ยฉ Greg Tang
b ac d 1st Sum
Final Answer
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 2
Name
For problems 1 and 2, estimate, and then find the sum.
1. 2 3 8 + ( 5 2 )
Date
2. 7.29 + (โ12.74)
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 33
EXIT TICKET 2
3. Noor uses decomposition to find
. Her work is shown. How does she use properties of operations in her work?
7โ8 โธ M1 โธ TA โธ Lesson 2 EUREKA MATH2 ยฉ Great Minds PBC 34 EXIT TICKET
3 4 9 + 7 5 9
3 4 9 + 7 5 9 = 3 + ( 4 9 ) + 7 + 5 9 = 3 + 7 + ( 4 9 ) + 5 9 = ( 3 + 7) + ( 4 + 5 99 ) = 4 + 1 _ 9 = 4 1 9
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 2
Name Date
KAKOOMAยฎ with Rational Numbers
In this lesson, we
โข estimated the sums of addition expressions.
โข used decomposition and properties of operations to add rational numbers.
โข evaluated addition expressions to solve and create puzzles.
Examples
For problems 1โ3, estimate, and then find the sum.
1. โ5 2 3 + 2 1 3
Estimation: โ6 + 2 = โ4
Sum:
The addends have opposite signs, so an effective strategy is to decompose one of the addends and use additive inverses.
Estimate the sum by rounding each addend to an integer. Then add the integers.
The additive inverse of 2 1 3 is โ2 1 3 . Decompose the rational number โ5 2 3 into 1 โ3 3 and โ2 1 3 to use additive inverses.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 35
RECAP 2
5 2 + 2 1 = 3 1 + ( 2 1 3333 ) + 2 1 3
= 3 1 3 + ( 2 1 3 + 2 1 3 ) = 3 1 3 + 0 = 3 1 3
2. โ15.6 + (โ3.25)
Estimation: โ16 + (โ3) = โ19
Sum:
โ15.6 + (โ3.25) = โ15 + (โ0.6) + (โ3) + (โ0.25)
= โ15 + (โ3) + (โ0.6) + (โ0.25)
= (โ15 + (โ3)) + (โ0.6 + (โ0.25))
= โ18 + (โ0.85)
= โ18.85
Apply the associative property of addition to group the integer parts together and the non-integer parts together.
3. โ21.4 + 18.45
Estimation: โ21 + 18 = โ3
Sum:
The addends have opposite signs.
The addends have the same sign, so decomposing each addend into its integer part and non-integer part is an effective strategy.
Apply the commutative property of addition to rearrange the integer parts and the non-integer parts.
The addends have opposite signs, so finding the difference between the absolute values of the two addends is an effective strategy.
The negative addend has the greater absolute value, so the sum is negative. The sum is โ2.95.
7โ8 โธ M1 โธ TA โธ Lesson 2 EUREKA MATH2 ยฉ Great Minds PBC 36 RECAP
21.4 โ 18.45 = 2.95
4. In the five-number pentagon, find the one number that is the sum of two other numbers.
It is not necessary to find the sum of every pair of numbers. Because 2 and 1 1 2 are the only two positive numbers and the sum of two positive numbers is a positive number, their sum is not one of the remaining numbers.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 37 RECAP
โ3โ1 4
โ3
โ1โ
1โ1 2 3 1 4 + 1 1 2 = 3 + ( 1 4 ) + 1 + 1 2 = ( 3 + 1) + ( 1 4 + 2 4 ) = 2 + 1 4 = 1 3 4 + ( 1 4 ) + 1 4 = 1 3 4
ยฉ Greg Tang
2
3 4
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 2
1. Jonas uses decomposition to find 7
. His work is shown. How does Jonas use properties of operations in his work?
2. Ava uses decomposition to find 8.14 + (โ8.34). Her work is shown. How does Ava use properties of operations in her work?
8.14 + (โ8.34) = 8.14 + (โ8.14) + (โ0.2)
= (8.14 + (โ8.14)) + (โ0.2)
= 0 + (โ0.2)
= โ0.2
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 39 PRACTICE 2 Name Date
2 + 5 1 33
7 2 + 5 1 = 7 + ( 2 333 ) + 5 + 1 3 = 7 + 5 + ( 2 3 ) + 1 3 = ( 7 + 5) + ( 2 + 1 33 ) = 2 + ( 1 3 ) = 2 1 3
For problems 3โ11, estimate, and then find the sum.
7โ8 โธ M1 โธ TA โธ Lesson 2 EUREKA MATH2 ยฉ Great Minds PBC 40 PRACTICE
3. 4 4 5 + ( 3 3 5 ) 4. โ20 1 3 + (โ2 1 4 ) 5. โ13.7 + (โ2.05) 6. โ10 2 3 + 4 1 6 7. โ5 1 8 + 1 3 4 8. 0.75 + (โ2.6)
9. 5.15 + (โ3.78)
11. 10 1 6 + (โ8 2 5 )
12. Yu Yan has $35.27 in her checking account. At midnight, debits of $12.82 and $4.93 will post to her account.
a. Write an addition expression to represent the situation. Then estimate the sum.
b. What is the value of the expression in part (a)?
c. What is the amount of money in Yu Yanโs checking account after the debits post?
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 41 PRACTICE
10. โ5 4 5 + 2 9 10
13. Ethan has $147.89 in his savings account. On the last day of the month, the bank posted a monthly service charge of $5.00 and interest earned of $0.49
a. Write an addition expression to represent the situation. Then estimate the sum.
b. What is the value of the expression in part (a)?
c. What is the amount of money in Ethanโs savings account after the transactions post?
14. Shawn evaluated the following expression but got an incorrect answer. Find and describe any errors Shawn made in his work.
7โ8 โธ M1 โธ TA โธ Lesson 2 EUREKA MATH2 ยฉ Great Minds PBC 42 PRACTICE
8 5 + ( 5 3 ) = 8 + 5 111111 + ( 5) + 3 11 = (8 + (โ5)) + ( 5 11 + 3 11 ) = 3 + 8 11 = 3 8 11
15. In each five-number pentagon, find the one number that is the sum of two other numbers. Use all five sums to create one final puzzle and solve.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 2 ยฉ Great Minds PBC 43 PRACTICE
Final Answer
b a c d e 3 1 โโ4 5 โ2โ3 5 โ1โ4 5 โ75 โ3 34 โ1 2 5 โ2 5 โ3 5 1โ1 5 1.31.1 0.4 โ0.7โ0.6 1.46.4 โ3.8 2.6โ2.4
ยฉ Greg Tang
Remember
For problems 16โ19, add.
20. Lily walks 60 feet in 10 seconds. Maya walks 25 feet in 5 seconds. Who walks at a faster rate? Explain how you know.
21. Which equation correctly models the following statement?
โ30 is 30 units from 0 on the number line.
A. (โ30) = 30
B. โ30 = 30
C. |30| = โ30
D. |โ30| = 30
7โ8 โธ M1 โธ TA โธ Lesson 2 EUREKA MATH2 ยฉ Great Minds PBC 44 PRACTICE
16. 1 3
5 3 17. 5 2
2 2 ) 18. 1 9 + ( 7 9 ) 19. 1 10 + ( 14 10 )
+
+ (
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 3
Name Date
Finding Distances to Find Differences
1. Write a conjecture about how to subtract integers by using the pattern you see in the displayed table. Explain how the pattern you see supports your conjecture.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 3 ยฉ Great Minds PBC 45
LESSON 3
Relating the Distance
For problems 2โ9, write the related unknown addend equation. Then use the number line to find the unknown addend. Record your answers in the columns labeled Unknown Addend Equation and Unknown Addend.
7โ8 โธ M1 โธ TA โธ Lesson 3 EUREKA MATH2 ยฉ Great Minds PBC 46 LESSON
โ10โ3 โ2 โ1โ4โ7 โ6 โ5โ8โ9108 7496 51 2 30 Subtraction Expression Distance Apart on the Number Line (units) Unknown Addend Equation Unknown Addend 2. 10 โ 8 3. 8 โ 10 4. 10 โ (โ8) 5. 8 โ (โ10) 6. โ10 โ 8 7. โ8 โ 10 8. โ8 โ (โ10) 9. โ10 โ (โ8)
Reasoning About Integer Subtraction
10. Consider the following sample work.
32 โ (โ45) = 32 โ 45 = โ13
a. Explain an error in the sample work.
b. Correctly evaluate the expression.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 3 ยฉ Great Minds PBC 47 LESSON
11. Sea level is represented by 0 feet. A gannet bird is at an elevation of 28 feet. It dives straight down to an elevation of โ19 feet to get a fish. How many feet does the gannet dive? Draw a model to represent the distance that the gannet dives.
7โ8 โธ M1 โธ TA โธ Lesson 3 EUREKA MATH2 ยฉ Great Minds PBC 48 LESSON
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 3
Name Date
1. Consider the expression 7 โ 12
a. Draw a number line and plot the integers in the expression.
b. What is the distance on the number line between the integers in the expression?
c. Write the expression as an unknown addend equation.
d. What is the unknown addend?
2. Consider the expression โ4 โ (โ10).
a. Draw a number line and plot the integers in the expression.
b. What is the distance on the number line between the integers in the expression?
c. Write the expression as an unknown addend equation.
d. What is the unknown addend?
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 3 ยฉ Great Minds PBC 49 EXIT TICKET 3
Name
Finding Distances to Find Differences
In this lesson, we
โข examined subtraction methods and their constraints when subtracting integers.
โข found the distance between the two numbers in a subtraction expression by plotting them on a number line.
โข wrote subtraction expressions as unknown addend equations and used a number line to model the equations.
โข found unknown addends by using a number line and drawing directed line segments.
Examples
1. Use the number line to plot points that represent A and B. State the distance between them. Then determine the number that should be added to A to get a sum of B.
To find the number to add to A to get B, it might be helpful to draw a directed line segment from A to B. Because the directed line segment from 6 to โ4 goes to the left and has a length of 10 units, it represents โ10 The number โ10 can be added to A to get a sum of B
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 3 ยฉ Great Minds PBC 51 RECAP 3
Date
A B Number Line Distance (units) Number Added to A to Get a Sum of B 6 โ4 โ10โ8โ6โ4 BA โ2100 2 4 6 8 10 โ10
โ10โ8โ6โ4 BA โ2100 2 4 6 8
Grade
Module 1, Topic A, Lesson 3
Student Edition:
7โ8,
2. Consider the expression โ4 โ 6.
a. Write the expression as an unknown addend equation.
6 + = โ4
Any subtraction expression can be written as an unknown addend equation. The value of the subtraction expression โ4 โ 6 is โ10, which is also the unknown addend that is added to 6 to get a sum of โ4 To determine the unknown addend, ask the question, What can be added to 6 to make โ4?
b. What must be added to 6 to get a sum of โ4? โ10
Because addition and subtraction are related, the unknown addend is also the difference of the subtraction expression.
6 + (โ10) = โ4
โ4 โ 6 = โ10
7โ8 โธ M1 โธ TA โธ Lesson 3 EUREKA MATH2 ยฉ Great Minds PBC 52 RECAP
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 3
For problems 1โ6, use the number line to plot points that represent A and B. State the distance between them. Then determine what must be added to A to get a sum of B.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 3 ยฉ Great Minds PBC 53
Name Date
PRACTICE 3
A B Number Line Distance (units) Number Added to A to Get a Sum of B 1. 7 โ2 โ2 โ4 โ6 โ8 โ10 10 8 64 20 2. โ2 7 โ2 โ4 โ6 โ8 โ10 10 8 64 20 3. โ7 โ2 โ10โ8 โ2 โ4โ60684210 4. โ7 2 โ2 โ4 โ6 โ8 โ10 10 8 64 20 5. โ2 โ7 โ10โ8 โ2 โ4โ60684210 6. 2 โ7 โ2 โ4 โ6 โ8 โ10 10 8 64 20
7. Consider the expression โ3 โ (โ2).
a. Write the expression as an unknown addend equation.
b. What must be added to โ2 to get a sum of โ3?
c. What is the value of the subtraction expression โ3 โ (โ2)? Explain how you know.
8. Consider the expression โ2 โ 9.
a. Write the expression as an unknown addend equation.
b. What must be added to 9 to get a sum of โ2?
c. What is the value of the subtraction expression โ2 โ 9? Explain how you know.
9. Consider the expression 4 โ (โ10).
a. Write the expression as an unknown addend equation.
b. What must be added to โ10 to get a sum of 4?
c. What is the value of the subtraction expression 4 โ (โ10)? Explain how you know.
7โ8 โธ M1 โธ TA โธ Lesson 3 EUREKA MATH2 ยฉ Great Minds PBC 54 PRACTICE
10. In Baltimore, the temperature is 35ยฐF. In Milwaukee, the temperature is โ7ยฐF. How much warmer in degrees Fahrenheit is it in Baltimore than in Milwaukee?
15. Use the number line to model the expression. Then determine the sum.
16. Determine the sum.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 3 ยฉ Great Minds PBC 55 PRACTICE
For problems 11โ14, add. 11. 1 5 + 3 6 12. 5 2 + 2 5 13. 4 9 2 + 3 14. 5 6 7 + 30
Remember
โ5 + 8 โ1010 9 8 7 6 5 4 3 2 1 0 โ1 โ2 โ3 โ4 โ5 โ6 โ7 โ8 โ9
โ5.3 + (โ4.5)
17. Complete each comparison by using <, >, or = .
a. 3 8 5 16
b.
c. 5.43 |โ6.2|
d.
e. |
7โ8 โธ M1 โธ TA โธ Lesson 3 EUREKA MATH2 ยฉ Great Minds PBC 56 PRACTICE
2โ83 1โ34
1.7 |โ4.32|
1
425
||
โ48
|
f. |โ3.21| |3.21|
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 4 LESSON
4
Subtracting Integers
Subtracting Negative Values
For problems 1โ6, complete the table. An example is provided.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 4 ยฉ Great Minds PBC 57
Name
Date
Subtraction Expression Equivalent Addition Expression Sign of the Value of the Expressions Value of the Expressions Example โ5 โ 3 โ5 + (โ3) Negative โ8 1. 2 โ 8 2. โ1 โ 6 3. โ4 + (โ5) 4. 3 โ (โ7) 5. โ9 + 4 6. โ9 โ (โ13)
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 4
Name Date
Write each expression as an equivalent addition expression. Then find the sum.
1. โ4 โ (โ20)
2. 7 โ (โ36)
3. โ44 โ 9
4. 37 โ 62
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 4 ยฉ Great Minds PBC 59 EXIT TICKET
4
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 4
Name Date
Subtracting Integers
In this lesson, we
โข represented subtraction expressions by using a number line and observed patterns to understand the relationship between subtraction and addition of integers.
โข determined the difference when subtracting a negative integer.
โข evaluated subtraction expressions by writing equivalent addition expressions.
Example
Complete the table. Write an equivalent addition expression and find the sum. Then write an unknown addend equation and find the unknown addend.
Subtraction expressions can be written as equivalent addition expressions. Change the subtraction sign to the addition sign and change the second integer to its opposite.
In this case, 16 โ 24 is written as 16 + (โ24).
Once a subtraction expression is written as an equivalent addition expression, use the integer addition strategies to find the sum.
When using unknown addend equations to check your work, ask this question: What number can I add to the second integer in the original subtraction expression to get the first integer?
In this case ask, What number can I add to โ6 to get โ21?
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 4 ยฉ Great Minds PBC 61
RECAP 4
Subtraction Expression Equivalent Addition Expression and Sum Unknown Addend Equation and Unknown Addend 16 โ 24 16 โ 24 = 16 + (โ24) = โ8 24 + = 16 24 + (โ8) = 16 โ21 โ (โ6) โ21 โ (โ6) = โ21 + 6 = โ15 โ6 + = โ21 โ6 + (โ15) = โ21
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 4
Name
1. Use the expression โ2 โ 5 to complete parts (a)โ(d).
a. Use the number line to model the expression.
Date
b. Write the subtraction expression as an equivalent addition expression.
c. Determine the sum of the expression from part (b).
d. Evaluate โ2 โ 5
2. Which expressions have the same value as โ16 โ 29? Choose all that apply.
A. 16 + (โ29)
B. โ16 + (โ29)
C. โ16 โ (โ29)
D. 16 โ 29
E. (0 โ 16) + (0 โ 29)
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 4 ยฉ Great Minds PBC 63
PRACTICE 4
For problems 3โ10, write an equivalent addition expression and find the sum. Then write an unknown addend equation and find the unknown addend.
Subtraction Expression
Equivalent Addition Expression and Sum
Unknown Addend Equation and Unknown Addend
7โ8 โธ M1 โธ TA โธ Lesson 4 EUREKA MATH2 ยฉ Great Minds PBC 64 PRACTICE
3. 12 โ (โ6) 4. 34 โ (โ19) 5. โ18 โ 4 6. โ45 โ 46 7. โ9 โ (โ9) 8. 25 โ 29 9. โ12 โ (โ5) 10. โ21 โ (โ30)
Remember
For problems 11โ14, add.
+
(
)
15. Estimate, and then find the sum.
16. Which expressions have a value of 105? Choose all that apply.
10 ร 5 B. 10 + 5 C. 10,000 D. 100,000
F. 10 + 10 + 10 + 10 + 10
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 4 ยฉ Great Minds PBC 65 PRACTICE
11. 2
3
5 6
12. 5 2 + 3 5 13. 8 9 + (โ 2 3 ) 14. โ 5 6 + 4 15
37 8 + ( 7 4 )
10 โ
10 โ
10 โ
10 โ
A.
E.
10
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 5
Name Date
Subtracting Rational Numbers
LESSON 5
1. Use the given number lines to model each subtraction expression. Then evaluate the expression. Write and solve an unknown addend equation to check your work.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 5 ยฉ Great Minds PBC 67
Subtraction Expression Model Difference Unknown Addend Equation 3 1 โ 44 โ1 1 0 0.75 โ (โ0.25) โ1 1 0 โ 3 โ 1 44 โ1 1 0 โ0.75 โ (โ0.25) โ1 1 0
Decomposing to Subtract
For problems 2โ4, evaluate the expression.
2. โ 4 2 โ 3 (โ 2 1 3 ) 3. โ
7โ8 โธ M1 โธ TA โธ Lesson 5 EUREKA MATH2 ยฉ Great Minds PBC 68 LESSON
1
4
3 1 2 )
โ
(โ
For problems 5โ8, evaluate the expression.
5. โ3.4 โ 2.1
6. 0.4 โ 1.4
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 5 ยฉ Great Minds PBC 69 LESSON 4. 5 1 โ 3 (โ 2 5 6 ) โ 3 2 3
7. โ2.7 โ 1.35 โ (โ6.25)
8. 1.85 โ 6.45 + 4.3
How Much?
9. Liam owes his grandmother $5.49. His grandmother tells Liam that she will remove $2.50 from his debt after he cleans the bathroom.
a. Write a subtraction expression that represents this situation.
b. Evaluate the expression from part (a). Explain what the result means in this situation.
7โ8 โธ M1 โธ TA โธ Lesson 5 EUREKA MATH2 ยฉ Great Minds PBC 70 LESSON
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 5
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 5 ยฉ Great Minds PBC 71 EXIT TICKET 5 Name Date
โ 4.7 โ (โ 3.7) 2. โ 3 โ 4 1 4 8
Evaluate each expression. 1.
3. 3 + (โ 0.2) โ 15.25
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 5
Subtracting Rational Numbers
In this lesson, we
โข used number lines and unknown addend equations to confirm that a subtraction expression involving rational numbers can be written as an equivalent addition expression.
โข used decomposition and properties of operations to make subtraction expressions simpler to evaluate.
โข evaluated subtraction expressions involving rational numbers.
โข wrote and evaluated a subtraction expression to represent a real-world situation.
Examples
For problems 1โ4, evaluate the expression.
Write the subtraction expression as an equivalent addition expression first.
Each mixed number canย be decomposed into an integer part and a non-integer part.
Use the commutative and associative properties of addition to rearrange the expression and to group the integers and non-integer parts together before evaluating.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 5 ยฉ Great Minds PBC 73 RECAP
5
Name Date
1. โ 5 1 โ 6 3 10 5 โ 5 1 โ 6 3 = โ 5 1 + 10 5 10 (โ 6 3 5 )
= โ 5 + (โ 1 10 ) + (โ 6) + (โ 3 5 )
= โ 5 + (โ 1 10 ) + (โ 6) + (โ 6 10 ) = (โ 5 + (โ 6)) + โ 1 + 10 (โ 6 10 ) ( )
= โ 11 + (โ 7 10 ) = โ 11 7 10 2. โ 7.43 โ (โ 4.31) โ 7.43 โ (โ 4.31) = โ 7.43 + 4.31 = โ 7 + (โ 0.43) + 4 + 0.31 A decimal can be decomposed
an integer part and a non-integer part. = (โ 7 + 4) + (โ 0.43 + 0.31) = โ 3 + (โ 0.12) = โ 3.12
and written as
When using the associative property, consider grouping negative
One strategy that is useful in this case is to decompose โ 0.46 into โ 0.45 + (โ0.01). That way, an additive inverse with 0.45 is created. Use the associative property of addition to group the additive inverses together.
7โ8 โธ M1 โธ TA โธ Lesson 5 EUREKA MATH2 ยฉ Great Minds PBC 74 RECAP 3. โ 4 3 โ 1 โ 8 4 (โ 2 1 2 ) โ 4 3 โ 1 โ (โ 2 1 ) = โ 4 3 + 8 4 2 8 (โ 1 4 ) + 2 1 2 = โ 4 + (โ 3 8 ) + (โ 1 4 ) + 2 + 1 2 = โ 4 + (โ 3 8 ) + (โ 2 8 ) + 2 + 4 8 = (โ ( 4 + 2) + โ 3 + (โ 2 88 )) + 4 8
addends together. = โ 2 + (โ 5 + 4 88 ) = โ 2 + (โ 1 8 ) = โ 2 1 8 4. โ 3.4 โ 0.06 โ (โ6.45) โ 3.4 โ 0.06 โ (โ 6.45) = โ 3.4 + (โ 0.06) + 6.45 = โ 3 + (โ 0.4) + (โ 0.06) + 6 + 0.45 = (โ 3 + 6) + (โ 0.4 + (โ 0.06)) + 0.45 = 3 + (โ 0.46) + 0.45 = 3 + (โ 0.45 + (โ 0.01)) + 0.45
= 3 + (โ 0.45 + 0.45)
(โ 0.01) = 3 + 0 + (โ 0.01) = 2.99
+
5. Vic owes his brother $4.28 for a snack and $7.43 for a shirt.
a. Write a subtraction expression that represents this situation.
โ 4.28 โ 7.43
Vic owes his brother $4.28, so that can be represented by โ 4.28.
b. Evaluate the expression from part (a). Explain what the result means in this situation.
โ 4.28 โ 7.43 = โ 4.28 + (โ 7.43)
= โ 4 + (โ 0.28) + (โ 7) + (โ 0.43)
= (โ 4 + (โ 7)) + (โ 0.28 + (โ 0.43))
= โ 11 + (โ 0.71)
= โ 11.71
Vic owes his brother $11.71
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 5 ยฉ Great Minds PBC 75 RECAP
Student Edition: Grade 7โ8, Module 1, Topic A, Lesson 5
PRACTICE 5
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 5 ยฉ Great Minds PBC 77
Name Date
1. โ 3 1 โ 3 55 2. 7.2 โ (โ6.1) 3. โ 2 1 โ 8 (โ 3 4 ) 4. โ 7.94 โ 10 5. โ 8.27 โ (โ 2.17) 6. 4 1 โ 5 (โ 1 1 10 )
For problems 1โ10, evaluate the expression.
7โ8 โธ M1 โธ TA โธ Lesson 5 EUREKA MATH2 ยฉ Great Minds PBC 78 PRACTICE 7. โ 0.03 โ (โ2.8) โ 11.97 8. โ 5 3 โ 1 โ 10 5 (โ 1 1 2 ) 9. 3 1 โ 10 3 + 4 1 2 8 4 10. โ 13.42 + 7.56 โ 1.2
11. Identify and correct the error in the sample work shown.
โ 1.23 โ (โ 5.26) = โ 1.23 + 5.26
= โ 1 + 0.23 + 5 + 0.26 = (โ1 + 5) + (0.23 + 0.26) = 4 + 0.49 = 4.49
12. Maya goes deep-sea diving. She first dives 18.28 meters below sea level. Then she dives down another 4.71 meters.
a. Write a subtraction expression that represents this situation.
b. Evaluate the expression from part (a). Explain what the result means in this situation.
Remember
For problems 13โ16, add.
EUREKA MATH2 7โ8 โธ M1 โธ TA โธ Lesson 5 ยฉ Great Minds PBC 79 PRACTICE
13. โ 5 + 3 3 5 14. 5 + 3 (โ 3 5 ) 15. 8 + 9 (โ 1 6 ) 16. โ 5 + 4 8 20
17. Consider the expression โ 8 โ (โ6).
a. Draw a number line and plot the integers in the expression.
b. What is the distance on the number line between the integers in the expression?
c. Write the expression as an unknown addend equation.
d. What is the unknown addend?
18. Complete each statement.
a. The opposite of โ 6 is .
b. The opposite of the opposite of โ 9 is .
c. The opposite of 0 is
d. The value of โ (โ 5 6 ) is .
7โ8 โธ M1 โธ TA โธ Lesson 5 EUREKA MATH2 ยฉ Great Minds PBC 80 PRACTICE
A Confusingly Cold Week Ugh. Itโs apparently going to be โ6o for the next three days. Thatโs too cold. Oh no! Thatโs โ18o in all!
Thatโs not how temperatures work. Oh, youโre right! I should *divide* by 3. Thatโs only โ2o! Still no.
Where do we see negative numbers in real life? Well, if you live in a cold climate, you may see them in your winter temperatures.
How cold are you when temperatures are negative? It depends on which system you use for measuring temperature. In degrees Celsius, โ1ยฐ is just below freezingโcold enough that youโll definitely want a jacket. But in degrees Fahrenheit, โ1ยฐ is absolutely frigid! Youโll need to cover your face if youโre outside for more than a few minutes.
Now can you explain the errors in the cartoon above? It may be trickier than it sounds!
ยฉ Great Minds PBC 81 Multiply
and Divide Rational Numbers TOPIC B
Student Edition: Grade 7โ8, Module 1, Topic B
Student Edition: Grade 7โ8, Module 1,
Topic B, Lesson 6
Name Date
Multiplying Integers and Rational Numbers
A Positive Number Times a Negative Number
1. An American football team has 3 consecutive plays where they lose 2 yards during each play.
a. Use a number line to model the situation.
b. Write an addition expression to represent this situation.
c. Write a multiplication expression to represent this situation.
d. Evaluate the expression from part (c) and explain the meaning of the product in this situation.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 83
LESSON 6
For problems 2โ5, determine the product. 2. 2(โ11)
A Negative Number Times a Positive Number
6. Complete the number sentences to make them true.
7โ8 โธ M1 โธ TB โธ Lesson 6 EUREKA MATH2 ยฉ Great Minds PBC 84 LESSON
3 1 โ ( 1) 2
1 โ ( 4.5) 2
3. 3(โ10) 4.
5.
2(2) = 4 1(2) = 2 0(2) = 0 โ1(2) = โ2(2)
โ3(2)
=
=
For problems 7โ9, use the commutative property to determine the product.
7. โ0.25(10)
8.
A Negative Number Times a Negative Number
For problems 10 and 11, complete the number sentences to make them true.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 85 LESSON
3 โ (7) 4
9 โ2 (1 โ3 )
9.
0(โ2)
0 โ1(โ2) = โ2(โ2) = โ3(โ2) =
10. 2(โ2) = โ4 1(โ2) = โ2
=
11.
2(โ10) = โ20
1(โ10) = โ10
0(โ10) = 0
โ1(โ10) =
โ2(โ10) =
โ3(โ10) =
12. Use properties to fill in the blanks to determine whether the conjecture is true or false.
Conjecture: (โ3)(โ2) = 6
Justification:
Line 1: (โ3)( ) = 0
Line 2: (โ3)(โ2 + ( )) = 0
Zero product property
Additive inverse
Line 3: (โ3)(โ2) + ( )( ) = 0 Distributive property
Line 4: (โ3)(โ2) + ( ) = 0
Line 5: + (โ6) = 0
Conclusion:
Product of a positive number and a negative number
Additive inverse
7โ8 โธ M1 โธ TB โธ Lesson 6 EUREKA MATH2 ยฉ Great Minds PBC 86 LESSON
Multiplication and Decomposition
For problems 13 and 14, evaluate the expression.
13. 4(โ 2 1 โ2 )
14. โ3(1.5)
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 87 LESSON
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 6
Name Date
1. Ethan is scuba diving. He descends 6 feet from the waterโs surface and rests. Then he descends another 6 feet and rests. Finally, he descends 6 more feet and examines a fish.
a. Use a number line to model the situation.
b. Write an addition expression to represent this situation.
c. Write a multiplication expression to represent this situation.
d. Evaluate the expression from part (c) and explain the meaning of the product in this situation.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 89 EXIT TICKET 6
For problems 2 and 3, determine the product.
2. 4(5)
3. 1 4 ( 1 1 2 )
7โ8 โธ M1 โธ TB โธ Lesson 6 EUREKA MATH2 ยฉ Great Minds PBC 90 EXIT TICKET
Name Date
Multiplying Integers and Rational Numbers
In this lesson, we
โข related repeated addition to multiplication to make sense of a multiplication expression where the first factor is positive and the second factor is negative.
โข analyzed patterns in tables to determine products.
โข used properties of operations to determine products of rational numbers.
โข applied decomposition and the distributive property to evaluate multiplication expressions.
Examples
Terminology
The zero product property states that if the product of two numbers is zero, then at least one of the numbers is zero.
This means that when โ
= 0, at least one of the factors is zero.
1. Lily is scuba diving. She descends 10 feet from the waterโs surface and rests. Then she descends another 10 feet and rests. Finally, she descends 10 more feet to reach a reef.
a. Use a number line to model the situation.
The directed line segments point down because each of them represents descending 10 feet. There are 3 of them because Lily descends 3 separate times.
The end of the last directed line segment represents Lilyโs depth below the waterโs surface when she reaches the reef.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 91
6
RECAP
0 โ30 10 10 10 โ10 โ20
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 6
b. Write an addition expression to represent this situation.
โ10 + (โ10) + (โ10) Because Lily descends 10 feet each time, the addends are โ10
c. Write a multiplication expression to represent this situation. 3(โ10) This multiplication expression describes an addition expression that has 3 groups of โ10
d. Evaluate the expression from part (c) and explain the meaning of the product in this situation.
โ30
The product โ30 means that Lily is 30 feet below the waterโs surface when she reaches the reef.
For problems 2โ5, determine the product.
โ24
The absolute value of 4 times the absolute value of โ6 is 24. The product of a positive number and a negative number is a negative number, so 4(โ6) = โ24.
The product of two negative numbers is a positive number.
7โ8 โธ M1 โธ TB โธ Lesson 6 EUREKA MATH2 ยฉ Great Minds PBC 92 RECAP
2. 4(โ6)
3. (โ4)(โ6) 24
4. (โ0.43)(6)
(โ0.43)(6) = (โ0.4 + (โ0.03))(6)
= (โ0.4)(6) + (โ0.03)(6)
= โ2.4 + (โ0.18) = โ2.58 5.
โ0.43 can be decomposed into โ0.4 and โ0.03
โ5
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 93 RECAP
(
After decomposing, use the distributive property. 1 4 )(โ20) ( 5 1 )( 20) = ( 5 + 4 ( 1 4 ))(โ20) โ5 1 4 can be decomposed into โ5 and โ 1 4 = ( 5)( 20) + ( 1 4 )( 20) = 100 + 5 = 105
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 6
Name
PRACTICE 6
Date
1. The temperature at 6:00 p.m. is โ4ยฐF. By 7:00 p.m., the temperature has dropped 4ยฐF. By 8:00 p.m., the temperature has dropped another 4ยฐF.
a. Use a number line to model the situation.
b. Write an addition expression to represent this situation.
c. Write a multiplication expression to represent this situation.
d. Evaluate the expression from part (c) and explain the meaning of the product in this situation.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 95
For problems 2 and 3, write the expression as repeated addition. Then evaluate the expression.
For problems 4โ19, determine the product.
7โ8 โธ M1 โธ TB โธ Lesson 6 EUREKA MATH2 ยฉ Great Minds PBC 96 PRACTICE
2. 4(2)
3. 4( 2)
4. 3( 6)
5. 3( 6)
6. 5( 4)
7. โ4(5)
8. 4( 5)
9. (โ6)(โ3) 10.
6( 3)
11. โ6(3)
Remember
For problems 20โ23, subtract.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 6 ยฉ Great Minds PBC 97 PRACTICE 12. 3 โ4 โ
16 13. 1 โ2 ( 9) 14. 0.4 โ
2 15. ( 0.38)( 5) 16. 2 โ3 (โ 4 โ5 ) 17. โ 1 โ2 (โ 5 โ8 ) 18. (โ2 1 โ3 )(โ12) 19. 0.2( 1.4)
20. 6 7 2 7 โ โ 21. 4 9 2 9 โ โ 22. 8 โ3 5 โ3 23. 12 14 2 14
For problems 24 and 25, write the expression as an equivalent addition expression and then evaluate.
24. 12 โ ( 46)
25. 14 โ 49
26. Evaluate the expression.
7โ8 โธ M1 โธ TB โธ Lesson 6 EUREKA MATH2 ยฉ Great Minds PBC 98 PRACTICE
5 3 โ4 + 2 1 โ2 1 โ4
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 7 LESSON
Exponential Expressions and Relating Multiplication to Division
Math Chat
For problems 1โ20, evaluate the expression.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 99
Date
7 Name
1. (โ3)(โ3) 2. (โ3)2 3. โ(3)2 4. โ(32) 5. โ(โ3)2 6. (1 3 )(1 3 ) 7. (1 _ 3 )2 8. (โ 1 _ 3 )(โ 1 _ 3 ) 9. (โ 1 3 )2 10. (โ 1 3 )(1 3 )
7โ8 โธ M1 โธ TB โธ Lesson 7 EUREKA MATH2 ยฉ Great Minds PBC 100 LESSON 11. โ(1 3 )2 12. (โ 4 5 )(5 7 )(3 8 ) 13. (โ1.1)(โ0.4) 14. (โ0.5)2 15. (โ1.5)2 16. (1.5)(โ1.5)2 17. (โ3)3 18. (โ 1 3 )3
Correcting the Errors
21. Use the given sample work to answer parts (a) and (b). (โ1.5)3 = (โ1.5)(โ1.5)(โ1.5) = โ2.25(โ1.5) = โ2.25(โ1 + 0.5) = โ2.25(โ1) + 2.25(0.5) = โ2.25 + 1.125 = 1.125
a. Explain an error in the sample work.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 101 LESSON 19. โ(1 3 )3 20. โ(โ 1 3 )3
b. Correctly evaluate the expression (โ1.5)3.
Relating Multiplication and Division
22. Complete the table.
7โ8 โธ M1 โธ TB โธ Lesson 7 EUREKA MATH2 ยฉ Great Minds PBC 102 LESSON
Division Expression Unknown Factor Equation Division Expression Evaluated Fraction Form Evaluated 8 รท 4 โ8 รท (โ4) โ8 รท 4 8 รท (โ4)
23. What is the process for dividing integers?
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 103 LESSON
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 7
Name
For problems 1 and 2, evaluate the expression.
1.
Date
For problems 3 and 4, write the unknown factor equation related to the expression and then determine the unknown factor.
3. โ20 รท 4
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 105
EXIT
TICKET 7
( 3 4 )3
2. โ( 2 3 )2
4. โ45 รท (โ5)
Name
Date
Exponential Expressions and Relating Multiplication to Division
In this lesson, we
โข predicted whether the value of a multiplication or exponential expression would be positive or negative.
โข evaluated exponential expressions that included negative numbers.
โข wrote unknown factor equations to divide integers.
Examples
For problems 1โ3, determine whether the value of the expression is positive or negative. Explain your answer.
1. (โ3)(0.5)(โ9)
The value of the expression is positive because there is an even number of negative factors.
2. (โ2) 3
The value of the expression is negative because there is an odd number of negative factors.
3. โ(โ4) 3
The value of the expression is positive because there is an even number of negative factors.
The base is โ2, and the exponent is 3 So there are 3 factors of โ2 (โ2)(โ2)(โ2)
The base is โ4, and the exponent is 3. So there are 3 factors of โ4. The negative sign outside the parentheses can be thought of as multiplying by โ1, so that makes 4 negative factors.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 107 RECAP 7
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 7
For problems 4โ7, evaluate the expression. 4. (
The exponent is 4, so there are 4 factors of
3 = (โ0.4)(โ0.4)(โ0.4) = 0.16(โ0.4) = โ0.064
The exponent is 3, so there are 3 factors of โ0.4 .
To determine the opposite of a number, multiply that number by โ1. Follow the order of operations by evaluating exponents before multiplication. So determine the value of 0.32 before taking the opposite.
The negative sign outside the parentheses represents taking the opposite of (
7โ8 โธ M1 โธ TB โธ Lesson 7 EUREKA MATH2 ยฉ Great Minds PBC 108 RECAP
2
3
4 ( 2 )4 = ( 2 )( 2 333 )( 2 )( 2 3 3 )
_
)
3 = 4 9 ( 2 3 )( 2 3 ) = โ 8 27 (โ 2 3 ) = 16 81
3
โ 2
5. (โ0.4)
6. โ0.3 2 โ0.3 2 = โ1 โ
0.3 2
(โ0.4)
= โ1 โ
0.09 = โ0.09 7. ( 1 5 )2 ( 1 )2 = ( 11 55 )( 5 )
1 5
2 = ( 1 25 ) = 1 25
โ
)
For problems 8 and 9, write the unknown factor equation related to the expression and then determine the unknown factor.
8. โ80 รท 4
The quotient of โ80 รท 4 is the number that is multiplied by 4 to get a product of โ80. The unknown factor is shown as a blank in the equation. โ20
4 โ
= โ80
โ15 โ
= โ60 4
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 109 RECAP
9. โ60 รท (โ15)
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 7
Name
Date
For problems 1โ7, determine whether the value of the expression is positive or negative. Explain your answer.
1. ( 4)( 1 2 )( 0.3)
2. ( 1 4)( 2 )(0.3)
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 111
PRACTICE 7
5
3. ( 1 4)( 2 )( 0.3)( 1) 4. ( 5) 2 5. ( 7)
For problems 8โ18, evaluate.
7โ8 โธ M1 โธ TB โธ Lesson 7 EUREKA MATH2 ยฉ Great Minds PBC 112 PRACTICE 6. ( 7) 5 7. (1 3 )4
8. ( 1 4 )( 1 4 ) 9. ( 3 4 )(3 4 ) 10. ( 0.2)( 1.5) 11. ( 6) 2 12. 6 2 13. ( 3 4 )2 14. ( 3 4 )2 15. 1.1( 1.1) 2
For problems 19โ22, write the unknown factor equation related to the expression and then determine the unknown factor. 19.
Remember
For problems 23โ26, subtract.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 7 ยฉ Great Minds PBC 113 PRACTICE
( 6) 3 17. ( 1 2 )4
1 10
4
16.
18. (
)
5
20 รท
20. 90 รท 3
21. 54 รท ( 9) 22. 77 รท ( 11)
23. 6 5 1 2 24. 8 9 2 5 25. 3 2 6 7 26. 8 3 8 5
For problems 27 and 28, evaluate.
27. 6.8 โ ( 2.9)
28. 7 _ 8 3 1 12
7โ8 โธ M1 โธ TB โธ Lesson 7 EUREKA MATH2 ยฉ Great Minds PBC 114 PRACTICE
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 8
Dividing Integers and Rational Numbers
Patterns in Integer Division
1. Complete the table by calculating each quotient with the values of p and q given in that row.
Division Expressions
For problems 2โ7, divide.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 8 ยฉ Great Minds PBC 115
Date
LESSON 8 Name
__ p q โ ___ p q ___ p q p โ (__ q ) ___ โp q p = 12 q = 3 p = โ 18 q = โ 2 p = 10 q = โ 5 p = โ 3 q = 4
2. 6 รท (โ 3 4 ) 3. (โ 0.9) รท (โ 0.4) 4. 1.96 โ 7 5. โ 4.5 โ 0.375 6. โ 18 รท 9 10010 7. โ 3 รท 0.8 10
For problems 8 and 9, evaluate the expression.
For problems 10โ12, divide.
7โ8 โธ M1 โธ TB โธ Lesson 8 EUREKA MATH2 ยฉ Great Minds PBC 116 LESSON
8. โ 2 (โ 12 โ (โ 9)) 3 9. 12 โ 4 + โ 1 โ 1 2
10. โ 3 4 24 25 11. 2 โ 3 1 6 12. โ 1 2 โ 3 5
Applications of Division
13. At 9 p.m., the temperature is 4ยฐF. At 6 a.m. the next morning, the temperature is โ 12ยฐF. Assume the temperature decreases at a constant rate. What is the approximate rate at which the temperature changes in degrees per hour?
14. A dolphin is underwater at an elevation of โ 10 feet. The dolphin swims down at a rate of โ 24 feet per minute. How long does the dolphin take to descend to an elevation of โ 286 feet?
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 8 ยฉ Great Minds PBC 117 LESSON
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 8
1. Which numbers shown are equivalent to โ 5 7 ? Circle all that apply.
For problems 2 and 3, divide.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 8 ยฉ Great Minds PBC 119 EXIT TICKET 8 Name Date
โ 5 7 โ 5 โ 7 โ (5 7 ) 7 5 5 7 5 โ 7 โ 7 5 โ (โ 5 โ 7 )
2. โ 2 รท (โ 0.6) 5 3. 1 2 3 5
Name Date
Dividing Integers and Rational Numbers
In this lesson, we
โข observed that the quotient of any two integers p and q can be written equivalently in different ways: โ p q = p โ q = โ ( p q ) if q โ 0.
โข wrote unknown factor equations to make sense of division expressions containing 0.
โข evaluated division expressions that contained rational numbers in fraction form and decimal form.
โข solved real-world problems by dividing rational numbers.
Examples
1. Evaluate โ a b for a = โ 5 and b = 4 โ (โ5) โ a = = 5 b 4 4
For problems 2โ6, divide.
Terminology
A rational number is any number that can be written in the form p q , where p and q are integers and q โ 0
A negative sign means taking the opposite. The expression โ (โ5) can be read as โthe opposite of โ 5,โ which is 5.
0 divided by any nonzero number has a quotient of 0
Think about the related unknown factor equation: โ 15 times what number equals 0? The unknown factor is 0. 3. โ 90 รท 0 Undefined
2. 0 รท (โ 15) 0 = 0 โ 15
When 0 is the divisor, the quotient is undefined. Think about the related unknown factor equation: 0 times what number equals โ 90? There is no such number, so the quotient is undefined.
Dividing by โ 5 4 has the same result as multiplying by its reciprocal, โ 4 5
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 8 ยฉ Great Minds PBC 121 RECAP 8
4. โ 5 รท โ 1 1 4 โ 5 รท โ 1 1 = โ 5 รท โ 5 44 = โ 5(โ 4 5 )
= 4
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 8
7. A fish swims at a constant rate from sea level to an elevation of โ 52 feet in 6 1 2 seconds. Write and evaluate a division expression to show the change in elevation of the fish in feet per second.
The elevation of the fish changes by โ 8 feet per second.
To find the rate of the fishโs change in elevation, divide the change in elevation in feet by the number of seconds the fish swims. The rate is negative because the elevation is decreasing.
7โ8 โธ M1 โธ TB โธ Lesson 8 EUREKA MATH2 ยฉ Great Minds PBC 122 RECAP 5. โ 4 9 ย รท 1.4 10 โ 4 9 รท 1.4 = โ 4.9 รท 1.4 10 Write โ 4 9 10 in decimal form, โ 4.9, and evaluate the expression by using decimal division. = โ 3.5 6. 4 โ 7 โ 2 3 โ (4 รท (โ 2 )) = โ (4 โ 3 7 3 7 ( 2 )) In the expression โ 4 7 โ 2 3 , 4 7 is the numerator and โ 2 3 is the denominator, so divide 4 7 by โ 2 3 . = โ (โ 12 14 ) = 12 14
โ 52 รท 6 1 = โ 52 รท 6.5 2
=
โ 8
Student Edition: Grade 7โ8, Module 1, Topic B, Lesson 8
Name Date
1. Which expressions are equivalent to โ 10 รท 5? Choose all that apply.
PRACTICE 8
2. Evaluate each expression for a = โ 3 and b = 6.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 8 ยฉ Great Minds PBC 123
A. โ 10 โ 5 B. โ 10 5 C. 10 โ 5 D. 10 5 E. โ 10 5
a. a b b. โ a b c. a โ b
For problems 3-10, divide.
7โ8 โธ M1 โธ TB โธ Lesson 8 EUREKA MATH2 ยฉ Great Minds PBC 124 PRACTICE
3. - 6 รท 1 1 3 4. 8 รท (-0.25) 5.3 รท 0 8 6. 0 รท (-1.8) 7. - 16.7 รท (-0.4) 8. - 1 1 25 6 9.3 รท (-0.15) 5 10. 2 1 รท (-0.375) 4
11. Evaluate.
2 3 (- 16 + 10 รท (- 2))
12. At 5 p.m., the temperature is 12ยฐF. At 5 a.m. the next morning, the temperature is - 9ยฐF. Assume the temperature decreases at a constant rate. At what rate does the temperature change in degrees per hour?
Remember
For problems 13-16, subtract.
For problems 17 and 18, determine the product.
17. - 8(7)
18.3 4 (- 1 1 3 )
19. Evaluate the expression.
EUREKA MATH2 7โ8 โธ M1 โธ TB โธ Lesson 8 ยฉ Great Minds PBC 125 PRACTICE
13. 71 12 3 14. 92 10 5 15. 133 16 4 16. 113 8 4
13 + (8 - 5)3 รท 3 + 6
Student Edition: Grade 7-8, Module 1, Topic B, Lesson 9 LESSON
Name
Decimal Expansions of Rational Numbers
Noraโs Method vs. Long Division
1. Nora says that she can use the prime factorization of the denominator to determine how to write a decimal fraction. Her work is shown. Explain Noraโs thinking.
For problems 2 and 3, use Noraโs method to write the number as a decimal fraction. Then write the decimal fraction as a decimal.
EUREKA MATH2 7-8 โธ M1 โธ TB โธ Lesson 9 ยฉ Great Minds PBC 127
9
Date
22 = 25 5 5 2 = โ
2 โ
2 5 โ
5 โ
2 โ
2 2 = โ
2 โ
2 (5 โ
2)(5 โ
2) 2 = โ
2 โ
2 10 โ
10 8 = 100
2. 3 - 8
3. 3 60
For problems 4 and 5, use the long division algorithm to verify that the decimal forms found in problems 2 and 3 are correct.
4. 3 - 8
5. 3 60
Repeating Decimals
For problems 6-8, use the long division algorithm to find the decimal form of the following rational numbers. Use bar notation when necessary.
7-8 โธ M1 โธ TB โธ Lesson 9 EUREKA MATH2 ยฉ Great Minds PBC 128 LESSON
6. 2 3 7. 5 - 6 8. 6 11
Student Edition: Grade 7-8, Module 1, Topic B, Lesson 9
EUREKA MATH2 7-8 โธ M1 โธ TB โธ Lesson 9 ยฉ Great Minds PBC 129 EXIT TICKET 9 Name Date Write the number as a decimal. Use bar notation where appropriate. 1. 15 6 2.4 25 3. 1 3 4.2 9 5.10 11 6. 7 15
Student Edition: Grade 7-8, Module 1, Topic B, Lesson 9
Name Date
Decimal Expansions of Rational Numbers
In this lesson, we
โข wrote rational numbers given in fraction form as decimals by first writing them as decimal fractions.
โข wrote rational numbers given in fraction form as decimals by using long division.
โข determined that a rational number can be written as a terminating decimal when the denominator has only prime factors of 2, 5, or both.
โข represented repeating decimals by using bar notation.
Examples
Terminology
A terminating decimal is a decimal that can be written with a finite number of nonzero digits.
A repeating decimal is a decimal in which, after a certain digit, all remaining digits consist of a block of one or more digits that repeats indefinitely.
A common notation for a repeating decimal expansion is bar notation. The bar is placed over the shortest block of repeating digits after the decimal point. For example, 3.125 is a compact way to write the repeating decimal expansion 3.12525252525โฆ .
1. Write12 25 as a decimal fraction. Then write it as a decimal.
A decimal fraction has a denominator that is a power of 10
To write decimal fractions as decimals, use the power of 10 in the denominator to determine the place value.
Create an equivalent fraction by multiplying both the numerator and the denominator by the same number.
Multiplying the denominator by 4 produces a power of 10.
EUREKA MATH2 7-8 โธ M1 โธ TB โธ Lesson 9 ยฉ Great Minds PBC 131 RECAP 9
12 =12 4 25 25 โ
4
48 100
=
= - 0.48
2. Factor the denominator of14 80 by using prime factorization. Write14 80 as a decimal fraction and then as a decimal.14 80
Factor the denominator into prime factors. If the prime factors are only 2, 5, or both, then the number can be written as a decimal fraction. This means it can be written as a terminating decimal.
Because decimal fractions have a denominator that is a power of 10, decimal fractions always have an equal number of factors of 2 and 5 in the denominator.
To write the number as a decimal fraction, multiply by additional factors of either 2 or 5 to produce a power of 10 in the denominator.
7-8 โธ M1 โธ TB โธ Lesson 9 EUREKA MATH2 ยฉ Great Minds PBC 132 RECAP
=
Divide the numerator and the denominator by any common factors so that their
common factor is 1. =7 2 โ
2 โ
2 โ
5
7 40
only
=7 โ
5 โ
5 2 โ
2 โ
2 โ
5 โ
5 โ
5 =7 โ
5 โ
5 (2 โ
5)(2 โ
5)(2 โ
5)
=175 10 โ
10 โ
10 =175 1,000 = - 0.175
For problems 3 and 4, write the number in decimal form. Use bar notation where appropriate.
3. 3 11
3 11 = 3 รท 11
To write fractions as decimals by using the long division algorithm, interpret the fraction as division. 0.2727 113. 00 00
Because the remainders begin to repeat, the quotients are repeating decimals.
0.27
The block of digits 2 and 7 repeats, so the bar is over both 2 and 7
4.17 1517 15 = - (17 รท 15)
1. 133 1517. 000 - 15 20 -15 50 -45 50 -45
3 is the only digit that repeats, so the bar is only over 3
5 -1.13
The quotient is a negative number because17 15 is interpreted as the opposite of the quotient 17 15 that produces.
EUREKA MATH2 7-8 โธ M1 โธ TB โธ Lesson 9 ยฉ Great Minds PBC 133 Recap
-22 80 -7 7 30 -2 2 80 -7 7 3
Student Edition: Grade 7-8, Module 1, Topic B, Lesson 9
Name Date
For problems 1 and 2, write the decimal in fraction form.
1. 0.58
2. โ 9.76
For problems 3-5, write the number as a decimal fraction. Then write it as a decimal.
3. โ 7 25
4. 31 20
5. โ 27 60
For problems 6 and 7, factor the denominator by using prime factorization. Write the number as a decimal fraction and then as a decimal.
6. 5 8
7. โ 21 40
EUREKA MATH2 7-8 โธ M1 โธ TB โธ Lesson 9 ยฉ Great Minds PBC 135
PRACTICE 9
For problems 8-13, indicate whether the decimal form of the number terminates or repeats.
For problems 14-20, use long division to write the number in decimal form. Use bar notation where appropriate.
7-8 โธ M1 โธ TB โธ Lesson 9 EUREKA MATH2 ยฉ Great Minds PBC 136 PRACTICE
Number Terminates Repeats 8. 5 7 9. 8 โ 3 10. 5 โ 18 11. 15 8 12. 40 75 13. โ 27 60
14. 4 9 15. 3 9 40 16. 19 15 17. โ 9 16 18. 43 60 19. โ 58 99
21. Henry says that every fraction with a denominator of 9 is a repeating decimal because the only factors of the divisor 9 are 3, not 2 or 5. Do you agree with Henry? Explain why.
22. Together, 6 friends buy a $20 gift for their other friend. How do the 6 friends share the cost of the gift evenly?
23. Is the decimal form of โ 9 6 a terminating decimal or a repeating decimal? Explain how you know.
EUREKA MATH2 7-8 โธ M1 โธ TB โธ Lesson 9 ยฉ Great Minds PBC 137 PRACTICE 20. โ 7 24
Remember
For problems 24-27, subtract.
For problems 28 and 29, evaluate the expression.
29.
30. Which expressions are equivalent to 2 (โ 4) 3 ? Choose all that apply.
A. 8 3
B. โ 8 3
C. โ 8 12
D. โ 2 3 (4)
E. 1 3 (โ8)
F. 4 3 (โ2)
7-8 โธ M1 โธ TB โธ Lesson 9 EUREKA MATH2 ยฉ Great Minds PBC 138 PRACTICE
24. โ 9 โ 1 20 2 25. โ 7 โ 3 16 4 26. โ 6 โ 3 5 4 27. โ 7 โ 1 8 4
โ
3
28. (
5 6 )
โ
2
( 9 10 )
Million, BillionโWhatโs the Difference, Really?
Thousand
About 17 minutes
Seconds
About 12 daysAbout 32 years
Feet
The rough length of a New York block
The rough distance from New York to Boston
The rough distance from New York to the moon
Dollars
About $0.03 every day of your life
About $35 every day of your life
People
A mid-sized high school
San Jose, CA (approximately)
About $35,000 every day of your life
The rough population of North and South America combined
Million and billion sound awfully similar. Just one letter is different. Written out as powers of 10, they look similar too: itโs 106 versus 109. How different can they really be?
Extremely different, it turns out.
If a million seconds is a long vacation, then a billion seconds is longer than your life so far. If a million feet is a short flight in an airplane, then a billion feet is a journey to the moon. If a million dollars over your lifetime is a nice daily allowance, then a billion dollars over your lifetime is enough to buy a new car every day. If a million people is the population of a big city, then a billion people is the population of the whole Western Hemisphere.
Exponents let us write huge numbers by using just a few symbols. But donโt let that fool you into forgetting how huge the numbers might be and how different they are from one another.
ยฉ Great Minds PBC 139
Student Edition: Grade 7-8, Module 1, Topic C TOPIC C Properties of Exponents and Scientific Notation
(103)(106)(109)
MillionBillion
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 10 LESSON
Name Date
Large and Small Positive Numbers
Writing Very Large and Very Small Positive Numbers
1. Complete the table. The table shows an approximate measurement of objects seen in the demonstration.
Approximate Measurement
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 10 ยฉ Great Minds PBC 141
10
Objects Standard Form Unit Form Single Digit Times a Power of 10 (expanded
Single Digit Times a Power of 10 (exponential form) Eiffel Tower (height) 300 Mount Everest (height) 9,000 Venus (width) 10,000,000
(meters)
form)
2. Complete the table. The table shows an approximate measurement of objects seen in the demonstration.
Approximate Measurement (meters)
Approximating Very Large and Very Small Positive Numbers
3. The length of Rhode Island, from the northernmost point to the southernmost point, is 77,249 meters.
a. Approximate the length of Rhode Island by rounding to the nearest tenย thousand meters.
b. Write your answer from part (a) as a single digit times a power of 10 in exponential form.
7โ8 โธ M1 โธ TC โธ Lesson 10 EUREKA MATH2 ยฉ Great Minds PBC 142 LESSON
Objects Standard Form Unit Form Fraction
Digit Times a Unit Fraction
Digit Times
Unit Fraction
Grape (width) 0.03 Grain of Rice (length) 0.006 Human Hair (width) 0.00008
Single
(expanded form) Single
a
(exponential form)
4. The width of a water molecule is 0.000ย 000ย 000ย 28 meters.
a. Approximate the width of a water molecule by rounding to the nearest ten billionth of a meter.
b. Write your answer from part (a) as a single digit times a unit fraction with a denominator written as a power of 10 in exponential form.
Times As Much As
5. 9 billion is how many times as much as 3,000?
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 10 ยฉ Great Minds PBC 143 LESSON
Record your work for each of the stations under the appropriate heading.
Station 1
Station 2
Station 3
Station 4
7โ8 โธ M1 โธ TC โธ Lesson 10 EUREKA MATH2 ยฉ Great Minds PBC 144 LESSON
Student Edition: Grade 7โ8, Module 1, Topic
Name Date
1. Consider the number 0.000ย 0285
a. Approximate the number by rounding to the nearest hundred thousandth.
b. Write your answer from part (a) as a single digit times a unit fraction with a denominator written as a power of 10 in exponential form.
2. Bacterial life appeared on Earth about 3.6 billion years ago. Mammals appeared about 200,000,000 years ago.
a. Write when bacterial life approximately appeared on Earth as a single digit times a power of 10 in exponential form.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 10 ยฉ Great Minds PBC 145 EXIT TICKET 10
C, Lesson 10
b. The number of years since bacterial life appeared on Earth is about how many times as much as the number of years since mammals appeared?
7โ8 โธ M1 โธ TC โธ Lesson 10 EUREKA MATH2 ยฉ Great Minds PBC 146 EXIT TICKET
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 10
Name
Large and Small Positive Numbers
In this lesson, we
Date
โข explored very large and very small positive numbers by relating them to the sizes of real-world objects.
โข analyzed equivalent forms of large and small positive numbers.
โข approximated very large and very small positive numbers.
โข wrote unknown factor equations to answer how many times as much as questions.
Examples
1. Complete the table. The table shows the approximate number of stacked pennies needed to reach the height of the Eiffel Tower.
Use place value units when writing numbers in unit form.
The expanded form of 2 hundred thousand is 2 ร 100,000, where the power of 10 is written in standard form.
The exponential formย of 1 hundred thousandย is 105, so write 2 hundred thousand as 2 ร 105
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 10 ยฉ Great Minds PBC 147 RECAP 10
Number of Stacked Pennies Object Standard Form Unit Form Single Digit Times a Power of 10 (expanded form) Single Digit Times a Power of 10 (exponential form) Eiffel Tower 200,000 2ย hundredย thousand 2 ร 100,000 2 ร 105
Approximate
2. Complete the table. The table shows the typical speed in miles per hour of a sea star.
3. The land area of France is 212,954 square miles. The land area of Canada is 3,854,083 square miles. The land area of Canada is about how many times as large as the land area of France?
Approximate the value of each land area. Then write the approximation as a single digit times a power of 10 in exponential form.
To decide how to write the unknown factor equation, determine which quantity is being multiplied. To determine the unknown factor, divide
The land area of Canada is about 20 times as large as the land area of France.
7โ8 โธ M1 โธ TC โธ Lesson 10 EUREKA MATH2 ยฉ Great Minds PBC 148 RECAP
Typical Speed (miles per hour) Object Standard Form Unit Form Fraction Single Digit Times a Unit Fraction (expanded form) Single Digit Times a Unit Fraction (exponential form) Sea Star 0.01 1ย hundredth 1 100 1 ร 1 100 1 ร 1 102
number in the Sea Star row is an equivalent form of 0.01. A unit fraction has a numerator of 1.
Each
212,954 โ 200,000
= 2 ร 105 3,854,083 โ 4,000,000 = 4 ร 106 4 ร 106 = โ
2 ร 105
4
4 ร 106 2 ร 105 = 4 ร 10 ร 10 ร 10 ร 10 ร 10 ร 10 2 ร 10 ร 10 ร 10 ร 10 ร 10 = 4 ร 10 ร 10 ร 10 ร 10 ร 10 ร 10 2 1010101010
of
the numerator and in the denominator.
the factors of
to
quotients of 10 10 , which is 1 = 2 ร 1 ร 1 ร 1 ร 1 ร 1 ร 10 = 2 ร 10 = 20
ร 106 by 2 ร 105
Write the factors
10 in
Then pair
10
create
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 10
Name Date
PRACTICE 10
1. Complete the table. The table shows the approximate number of stacked pennies needed to reach the height of the given objects.
Approximate Number of Stacked Pennies
Objects
Single Digit Times a Power of 10 (expanded form)
Single Digit Times a Power of 10 (exponential form) Mount Everest 6,000,000 Empire State
2. Complete the table. The table shows the typical speed of the given animals.
Typical Speed (miles per hour)
Objects
Galapagos Tortoise 0.2
Sloth 0.07
Single Digit Times a Unit Fraction (expanded form)
Single Digit Times a Unit Fraction (exponential form)
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 10 ยฉ Great Minds PBC 149
Unit
Standard Form
Form
Building 300,000
Unit Form
Standard Form
Fraction
3. There are 907,200,000 milligrams in 1 ton.
a. Approximate the number of milligrams in 1 ton by rounding to the nearest hundred million milligrams.
b. Write your answer from part (a) as a single digit times a power of 10 in exponential form.
4. The smallest insect on the planet is a type of parasitic wasp that measures 0.000 139 meters.
a. Approximate the length of the insect by rounding to the nearest ten thousandth of a meter.
b. Write your answer from part (a) as a single digit times a unit fraction with a denominator written as a power of 10 in exponential form.
5. 800,000 is how many times as much as 2,000?
6. 60,000,000ย is how many times as much as 30,000?
7. 6 ร 105 2 ร 103 is times as much as what number?
7โ8 โธ M1 โธ TC โธ Lesson 10 EUREKA MATH2 ยฉ Great Minds PBC 150 PRACTICE
For problems 8 and 9, use the values in the table to answer the questions.
8. Based on land area, about how many islands the size of Jamaica does it take to equal the size of Russia?
9. Which countryโs land area is about 1 500 as large as the land area of the United States?
10. The Atlantic Ocean contains about 310,410,900 cubic kilometers of water. Lake Superior, which is the largest lake in the United States, contains about 12,000 cubic kilometers of water. Approximately how many Lake Superiors would it take to fill the Atlantic Ocean?
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 10 ยฉ Great Minds PBC 151 PRACTICE
Location Russia United States Brazil Belize Slovenia Jamaica Approximate Land Area (square miles) 7 ร 106 4 ร 106 3 ร 106 9 ร 103 8 ร 103 4 ร 103
Remember
For problems 11โ14, subtract.
(
)
For problems 15 and 16, divide.
17. Find the value of the expression shown.
7โ8 โธ M1 โธ TC โธ Lesson 10 EUREKA MATH2 ยฉ Great Minds PBC 152 PRACTICE
11. 8 โ 15
โ 4 5
12. 7 โ 10 (โ 2 5 ) 13. โ 5 โ 6 (โ 3 4 ) 14. โ 7 โ 5 (โ 4 6 )
15. โ 3 รท (โ0.5) 5 16. โ 1 8 4 5
โ 1 รท 2 โ
4 3 (โ 1 2 5 )
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 11
Name Date
Products of Exponential Expressions with Positive Whole-Number Exponents
1. Multiply. Write the product as a power of 10 in exponential form.
Multiplying Powers with Like Bases
2. Multiply. Write the product as a power of 10 in exponential form.
3. Multiply. Write the product as a power of 10 in exponential form.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 ยฉ Great Minds PBC 153
LESSON 11
โ
1020
1050
โ
102
105
โ
10342
1057
Applying a Property of Exponents
For problems 4โ15, apply the product of powers with like bases property to write an equivalent expression.
7โ8 โธ M1 โธ TC โธ Lesson 11 EUREKA MATH2 ยฉ Great Minds PBC 154 LESSON
4. 53 54 5. (โ 5)6 (โ 5)10 6. (โ 2 3 )7 โ
(โ 2 3 )5 7. y 8 โ
y 11 8. 5.823 โ
5.88 9. a 23 โ
a 8 10. 7210 โ
72 11. f 10 โ
f 12. (5 9 )22 โ
(5 9 )78 13. 22 (b 2 ) โ
(b 2 )78 14. (โ 3)9 โ
(โ 3)6 15. 2 x 6 โ
3 x 5 16. Solve for x 74 โ
7x = 712
17. Write three exponential expressions that are equivalent to 916.
18. Which expressions have a value of โ 16? Choose all that apply.
A. โ 1 โ
24
B. โ 24
Multiplying Powers with Unlike Bases
For problems 19โ21, apply the product of powers with like bases property to write an equivalent expression.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 ยฉ Great Minds PBC 155 LESSON
C. (โ 2)4
D. โ (24)
E. โ (โ 2)4
F. (โ 2)2 โ
(2)2
19. 93 โ
94 โ
42 โ
4 20. (โ2)2 195 197 (โ 2)3 21. 4 104 105
Properties of Exponents
Definitions of Exponents
ยฉ Great Minds PBC 157 EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 โธ Properties and Definitions of Exponents
Description Property Example
Description Definition Example
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 11
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 11
For problems 1โ4, apply the product of powers with like bases property to write an equivalent expression. 1.
5. Explain what the expression 43 โ
46 represents and how it can be written as a single power.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 ยฉ Great Minds PBC 159 EXIT TICKET
11 Name Date
56
(โ 5)3 (โ 5)8
(3 5 )4(3 5 )
5a โ
5b
53 โ
2.
3.
4.
Name
Products of Exponential Expressions with Positive Whole-Number Exponents
In this lesson, we
โข discovered a pattern when multiplying powers with like bases.
โข learned the product of powers with like bases property.
โข applied a property of exponents to write equivalent expressions.
Product of Powers with Like Bases Property
Examples
Apply a property of exponents to write an equivalent expression. 1.
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 11 = 96
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 ยฉ Great Minds PBC 161 RECAP 11
Date
x m . x n = x m+n when x is any number m and n are positive whole numbers
โ
92 94 โ
92
94+2 94 . 92 = 9 . 9 . 9 . 9 . 9 . 9 4 times 2 times
4 is 4 factors of 9
2 is 2 factors of 9
94 . 92 is 4 + 2 factors of 9, which can be written as 94+2 .
94
=
9
9
So
Negative bases and fractional bases have parentheses to avoid confusion.
The first factor represents 1 factorof (โ 1 6 ), so it has an exponent of 1
Because there are two different bases, 7 and 8, use the commutative property of multiplication to rearrange the powers with like bases together. Then apply the property of exponents to powers with like bases separately.
7โ8 โธ M1 โธ TC โธ Lesson 11 EUREKA MATH2 ยฉ Great Minds PBC 162 RECAP 2. 1 (โ 6 )(โ 1 6 )3
(โ 1 6 )(โ 1 6 )3 = (โ 1 6 )1+3
= (โ 1 6 )4 3. 74 โ
83 โ
74 โ
84 74 โ
83 โ
74 โ
84 = 74 โ
74 โ
83 โ
84
= 74+4 โ
83+4
= 78 87
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 11
PRACTICE 11
For problems 1โ10, apply the product of powers with like bases property to write an equivalent expression.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 ยฉ Great Minds PBC 163
Name Date
1. 106 โ
105 2. 24 โ
23 โ
22 3. (โ4)8 (โ4)2 4. (โ y)8 (โ y)10 (โ y)6 5. 32 โ
3 6. ( 1 10 )15 ( 1 10 )16 7. ) 5 ( 1 5(1 a ) 1 a (1 a ) (a ) 8. 1010 โ
108 โ
(โ2)7 โ
(โ2)9 9. d 3 โ
c โ
c โ
d 3 10. (1 )28 (1 )24 (1 4 )26 1 30 2 2 (4 )
11. Which expressions are equivalent to 53 โ
55? Choose all that apply.
A. 53+5
B. 53 5
C. 58
D. 515
E. 54 โ
54
F. 258
12. Which expressions are equivalent to 912? Choose all that apply.
A. 36 โ
36
B. 99 โ
93
C. 94 โ
93
D. 9 โ
912
E. 96 โ
96
F. 96 โ
92
13. Sara states that when two powers with the same base are multiplied, the exponents are multiplied together. She uses an example to support this claim.
Fill in the boxes to create an equation that shows that Saraโs claim is incorrect.
7โ8 โธ M1 โธ TC โธ Lesson 11 EUREKA MATH2 ยฉ Great Minds PBC 164 PRACTICE
โ
โ
42
42 = 42
2 = 44
4
4
4 โ
=
14. Write the area of the rectangle as a single base raised to an exponent.
105ft
102ft
For problems 15โ18, indicate whether the value of the expression is a positive number or a negative number.
15. (โ 3)2
16. (โ 4)3
17. (โ 5)133
18. (โ 6)4,592
19. The product (โ 1)3 โ
(โ 1)n is a negative number. Which of the following values of n are possible? Choose all that apply. A.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 ยฉ Great Minds PBC 165 PRACTICE
7
8
10
2 B. 5 C.
D.
E.
For problems 20โ23, solve for b.
For problems 24โ26, fill in the boxes with digits 1โ6 to make the equation true. Each digit can be used only once.
Remember
For problems 27โ30, multiply.
7โ8 โธ M1 โธ TC โธ Lesson 11 EUREKA MATH2 ยฉ Great Minds PBC 166 PRACTICE
20. 3b = 311 โ
33 21. 7b โ
74 = 712 22. 4 โ
4b = 46 23. 65 โ
63 = 62b
24. x 2 โ
4 x = 8 x 6 25. (2 x )(3x) = x 2 26. (x 4 y 2)(xy) = xy
27. 1 โ
6 3 28. 6(โ 2 3 ) 29. โ 10(2 5 ) 30. 4 โ
14 7
For problems 31โ34, write each number as a decimal. Use bar notation where appropriate.
31. โ 36 1,000
32. โ 9 25
33. โ 7 9
Estimate, and then find the quotient.
35. 85.92 รท 12
34. 5 11
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 11 ยฉ Great Minds PBC 167 PRACTICE
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 12 LESSON
Name Date
More Properties of Exponents
Raising Powers to Powers
Raising Products to Powers
Raising Quotients to Powers
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 12 ยฉ Great Minds PBC 169
12
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 12
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 12 ยฉ Great Minds PBC 171 EXIT TICKET 12 Name Date
the properties
an equivalent expression. Assume y is nonzero. 1. (9 3 ) 6 2. (2 x) 4 3. 3( 4 y )2
Apply
of exponents to write
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 12
Name Date
More Properties of Exponents
In this lesson, we
โข established two new properties of exponents.
โข used the properties of exponents to write equivalent expressions.
Power of a Power Property
Power of a Product Property (xy)
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 12 ยฉ Great Minds PBC 173 RECAP 12
and n
(xm)n = xm.n when x is any number m
are positive whole numbers
n = xnyn when x and y are any numbers n is a positive whole number
Apply the properties of exponents to write an equivalent expression.
Both the numerator, 9 2 , and the denominator, 10, are raised to the sixth power.
Both factors have a power of 3, so there are 3 factors of 2 and 3 factors of 5. By using the commutative and associative properties of multiplication, this expression can be written as 3 factors of (2
5), which is 10 3
7โ8 โธ M1 โธ TC โธ Lesson 12 EUREKA MATH2 ยฉ Great Minds PBC 174 RECAP
1. (w 2 ) 3 3 times (w2)3 = w2 w2 w2 = w2+2+2 = w3.2 (w 2 ) 3 is
factors of
, which is 3 โ
2 factors of w. w 6 3. 9 ( 2 10 )6
3 factors of w 2 . This is 3
2 factors of w
( 9 2 )6 = 9 2 9 2 9 2 โ
โ
9 2 โ
9 2 โ
9 2 โ
1010 10 10 10 10 10 912 106 2. (3r 7 ) 4 The entire term 3r 7 is raised to the fourth power 4 times (3r7)4 = 3r7 . 3r7 . 3r7 . 3r7 3 4 r 28 4. 23 โ
53
โ
23 โ
53 = (2 โ
2 โ
2) โ
(5 โ
5 โ
5) = (2 โ
5) โ
(2 โ
5) โ
(2 โ
5) = (2 โ
=
103
5)3
103
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 12
PRACTICE 12
For problems 1โ10, apply the properties of exponents to write an equivalent expression. Assume m is nonzero.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 12 ยฉ Great Minds PBC 175 Name Date
1. (3 4 ) 5 3. (6 7 b 8 ) 9 5. (dg) 11 7. (3 8 4 6 )6 9. n ( 3 m 7 )5 2. (a 2 ) 3 4. (8 c) 9 6. ( fg 2 h 3 ) 4 8. 1 (10 2 )13 10. ((p 2 ) 4 ) 6
11. Jonas says (5n 2 ) 3 is equivalent to 5n 2 3. Do you agree? Explain your reasoning.
In problems 12โ16, fill in the boxes with values that make the equation true. Assume s is nonzero.
7โ8 โธ M1 โธ TC โธ Lesson 12 EUREKA MATH2 ยฉ Great Minds PBC 176 PRACTICE
12. (a 3 b 4 ) = a 6 b 13. 2 (r s 3 ) = r 10 s 14. ( ร 10 5 ) 2 = 9 ร 10 15. 34 โ
( )4 = 64
16. 6 106 = (1 2 )6
17. Which expressions are equal to 8 24 ? Choose all that apply.
A. (8 20 ) 4
B. (8 12 ) 2
C. 8 8 โ
8 3
D. 8 14 โ
8 10
E. 8 8 + 8 16
18. Which expressions are equal to x 12 y 8 z 4 ? Choose all that apply.
A. (x 8 y 6 z) 4
B. (x 3 y 2 z) 4
C. (x 6 y 4 z 2 ) 2
D. (x 3 y 4 z 2 )(x 4 y 2 z 2 )
E. (x 6 y 5 z)(x 6 y 3 z 3 )
19. The edge of a cube measures 4 n 2 inches. What is the volume of the cube?
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 12 ยฉ Great Minds PBC 177 PRACTICE
20. The side length of a square measures meters. What is the area of the square? 3 x 4 y 5 Assume y is nonzero.
Remember
For problems 21โ24, multiply.
25. There are 0.000 000 001 102 293 tons in 1 milligram.
a. Approximate the number of tons in 1 milligram by rounding to the nearest billionth of a ton.
b. Write your answer from part (a) as a single digit times a unit fraction with a denominator written as a power of 10 in exponential form.
26. The world population is expected to reach about 9.7 billion people in the year 2050.
a. Approximate the expected world population in 2050 by rounding to the nearest billion people.
b. Write your answer from part (a) as a single digit times a power of 10 in exponential form.
c. The population of the United States is expected to reach about 400 million people in the year 2050. The expected world population in 2050 is about how many times as much as the expected United States population in 2050?
7โ8 โธ M1 โธ TC โธ Lesson 12 EUREKA MATH2 ยฉ Great Minds PBC 178 PRACTICE
21. โ 1 โ
5 3 22. 6(2 5 ) 23. โ 10(โ 2 3 ) 24. โ 4 โ
8 7
27. Consider the rational number โ 5 9 .
a. Is the decimal form of 5 9 a terminating decimal? Explain how you know.
b. Write โ _ 5 9 in decimal form.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 12 ยฉ Great Minds PBC 179 PRACTICE
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson
Making Sense of Integer Exponents
1. Circle all expressions that have a value of 1. Assume x is nonzero.
Integer Exponents
For problems 2โ5, use the definition of a negative exponent to write an equivalent expression with a positive exponent. Assume x is nonzero.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 13 ยฉ Great Minds PBC 181
Name Date
13
LESSON
60 (โ6)0 0 โ
60 10 60 6 (1 6 )0 10 60 6 x 0 (6 x)0
4.
13
2. 10โ7
xโ8 3. (โ5)โ9 5. 1 10โ2
Quotients of Powers
6.
So-hee applies the properties of exponents to write an equivalent expression for . Her work is shown.
Apply the properties and definitions of exponents to verify So-heeโs answer.
For problems 7 and 8, apply the properties and definitions of exponents to write an equivalent expression with only positive exponents. Assume d is nonzero.
7โ8 โธ M1 โธ TC โธ Lesson 13 EUREKA MATH2 ยฉ Great Minds PBC 182 LESSON
103 107
103 107 = 103 103 104 3 = 10 103 1 โ
104 = 1 104
7. 813 821 8. 7d 4 14d7
tudent Edition: Grade 7โ8, Module 1, Topic C, Lesson 13
For problems 1 and 2, apply the definition of the exponent of 0 to write an equivalent expression. 1.
3. Use the definition of a negative exponent to write 5โ7 with a positive exponent.
4.
Kabir and Yu Yan each write an equivalent expression for . The table shows their work.
Explain how Kabir and Yu Yan each use the properties and definitions of exponents to get the final expression.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 13 ยฉ Great Minds PBC 183
Name Date EXIT
TICKET 13
3
โ
0
(2
)0 2. 7
x
89 85
Kabirโs Work Yu Yanโs Work 89 85 = 85 โ
84 85 5 = 8 85 โ
84 = 84 89 85 = 89 โ
8โ5 = 89+(โ5) = 84
S
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 13
Name
Making Sense of Integer Exponents
In this lesson, we
Date
โข used the product of powers with like bases property to determine that x 0 = 1.
โข related negative exponents to multiplicative inverses.
โข learned the definition of a negative exponent.
โข applied the definition of a negative exponent to write equivalent expressions.
Definition
Definition of a Negative Exponent
Examples
1. Write an equivalent expression for
is nonzero. 5
The exponent of 0 applies only to the base c, not to the entire expression 5c
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 13 ยฉ Great Minds PBC 185
RECAP 13
x is nonzero x 0=1
of the Exponent of 0
x โn = 1 x n when
nonzero n is an integer
x is
c 0.
c
c 0 = 5 โ
c 0
โ
5
Assume
= 5
1 = 5
2. Without using the definition of a negative exponent, how can we show 10 1 โ5 = 105 ?
By using the product of powers with like bases property and the definition of the exponent of 0, we know 105 10โ5 = 105+(โ5) = 100 = 1.
We also know 10 1 5 โ
105 = 1
This means 10โ5 and 1 105 are both multiplicative inverses of 105. So 10โ5 = 1 105
Two factors that have a product of 1 are multiplicative inverses.
For problems 3 and 4, use the definition of a negative exponent to write an equivalent expression with a positive exponent.
A fraction represents division.
7โ8 โธ M1 โธ TC โธ Lesson 13 EUREKA MATH2 ยฉ Great Minds PBC 186 RECAP
3. 17โ4 1 17 4
4. 1 5โ3 1 5โ3 = 1 รท 5โ3
= 1 รท __ 1 53 3 = 1 5 1 = 53
___
5. Apply the properties and definitions of exponents to write an equivalent expression with only positive exponents. Assume r is nonzero.
To use the product of powers with like bases property, write
5
11 as r 5 r โ11. Then use the definition of a negative exponent to write the answer with a positive exponent.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 13 ยฉ Great Minds PBC 187 RECAP
2 r 5 16 r 11 2 r 5 16 r 11 = 2 16 r 5 r 11 = 2 16 โ
r 5 โ
r โ11 = 1 8 โ
r 5+(โ11) = 1 8 r โ6 = 1 8r 6 2 r 5 16 r 11 = 2 r 5 16 r 11 5 = 2 r โ
16 r 5 โ
r 6 5 = 1 โ
r 8 r 5 1 โ
r 6 = 1 1 โ
8 r 6 = 1 8r 6
To make a quotient of r 5 r 5 , or 1, write r 11 as r 5 r 6
r
r
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 13
For problems 1โ15, apply the properties and definitions of exponents to write an equivalent expression with only positive exponents. Assume all variables are nonzero.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 13 ยฉ Great Minds PBC 189 Name Date
PRACTICE 13
1. 20 4. (โ 3 10 f) 0 7. x โ10 10. (โ 6) โ3 13. 1 f โ3 2. 110 โ
113 5. (โ4)2 (โ 4)0 8. ( h0 k)8 11. 108 105 14. 3 36 3. 10โ5 6. (2 9 )0 (2 9 )0 9. 6 20 63 60 2 22 12. 6 โ
6 โ5 15. 8t 2 24t 9
For problems 16โ19, apply the properties and definitions of exponents to determine the value of t.
For problems 20 and 21, write a number in the box to make the equation true.
22. Choose the expression that has a value of 9,804.
A. 9 ร 103 + 8 ร 102 + 4 ร 101
B. 9 ร 104 + 8 ร 103 + 4 ร 101
C. 9 ร 104 + 8 ร 103 + 4 ร 100
D. 9 ร 103 + 8 ร 102 + 4 ร 100
23. What is the value of 6 ร 104 + 3 ร 102 + 2 ร 100?
A. 632
B. 6,032
C. 6,320
D. 60,302
E. 60,300
7โ8 โธ M1 โธ TC โธ Lesson 13 EUREKA MATH2 ยฉ Great Minds PBC 190 PRACTICE
80 โ
82
t 18. 25 โ
20 = t 17. (3 )0 (3 8 8 )t = (3 8 )11 19. (โ 0.25)0 (โ 0.25)t = 1
16.
= 8
20. (โ 2)0 (โ 2)= (โ 2) 5 21. (1 4 )(1 4 )0 = 1
24. Maya says 10โ5 is equivalent to (โ 10)5. Do you agree? Explain your reasoning.
25. Which expression does not have a value of 1 16 ?
26. Order the values from least to greatest.
Remember
For problems 27โ30, multiply.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 13 ยฉ Great Minds PBC 191 PRACTICE
A. 411 413 B. 4 42 C. 4โ2 D. 25 29
(โ1)5 5โ1 10 0 0.1 1 โ1 3โ6 โ
38 26 4 25
27. 6 โ
5 _ 5 2 28. โ 3 _ โ
16 __ 4 6 29. 10 (โ __ 3 )(โ __ 6 20 ) 30. โ 4 _ โ
21 __ 7 2
For problems 31 and 32, apply the product of powers with like bases property to write an equivalent expression.
31. (2 7 )4 (2 7 )8
32. 9a โ
9b
33. Explain what the expression 53 57 represents and how it can be written as a single power.
34. Write 17 16 in decimal form.
7โ8 โธ M1 โธ TC โธ Lesson 13 EUREKA MATH2 ยฉ Great Minds PBC 192 PRACTICE
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 14
Name
Writing Very Large and Very Small Numbers in Scientific Notation
Archimedes was a Greek mathematician whose ideas were ahead of his time. He lived in Sicily during the third century BCE and was the first to develop fundamental concepts in geometry, calculus, and physics.
Fascinated by very large numbers and living on the coast of the Ionian Sea, Archimedes set out to determine how many grains of sand are needed to fill the known universe.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 193
Date LESSON 14
Mathematicians used Ionic Greek notation in the third century BCE. So instead of numbers, they used symbols and letters from the Greek alphabet.
1. In this system, ฯฮฝฮด represents the number 654. What does ฯฯฮต represent?
2. What does ฯฮฟฮถ represent?
Another Way to Represent Numbers
3. Fill in the blanks to complete the statements.
A number is written in scientific notation when it is represented as a numberย a multiplied by a of .
The general expression that represents a number written in scientific notation is ร .
The absolute value of a must be at but than
7โ8 โธ M1 โธ TC โธ Lesson 14 EUREKA MATH2 ยฉ Great Minds PBC 194 LESSON
name symbol value alpha ฮฑ 1 beta ฮฒ 2 gamma ฮณ 3 delta ฮด 4 epsilon ฮต 5 digamma ฯ 6 zeta ฮถ 7 eta ฮท 8 theta ฮธ 9 name symbol value iota ฮน 10 kappa ฮบ 20 lambda ฮป 30 mu ฮผ 40 nu ฮฝ 50 xi ฮพ 60 omicron ฮฟ 70 pi ฯ 80 koppa ฯ 90 name symbol value rho ฯ 100 sigma ฯ 200 tau ฯ 300 upsilon ฯ
400 phi ฯ 500 chi ฯ 600 psi ฯ 700 omega ฯ 800 sampi ฯก 900
4. Identify the first factor and the order of magnitude of the expression 8.86 ร 106.
5. Indicate whether each number is written in scientific notation.
0.38 ร 102 4.8 ร 103 19.04 ร 107 โ 6.75 ร 106
ร 109
ร 1010
For problems 6โ11, complete the table.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 195 LESSON
Number Yes No
1
10
Number in Standard Form Number in Scientific Notation 6. 400,000 7. 2 ร 104 8. โ 2.7 ร 104 9. 2.35 ร 106 10. โ 525,000 11. 2.05 ร 106
Small Positive Numbers
12. Complete the table.
Approximate
7โ8 โธ M1 โธ TC โธ Lesson 14 EUREKA MATH2 ยฉ Great Minds PBC 196 LESSON
Measurement (meters) Objects Standard Form Unit Form Fraction Single Digit Times a Unit Fraction (expanded form) Single Digit Times a Unit Fraction (exponential form) Scientific Notation Grape (width) 0.03 3 hundredths 3 100 1 3 ร 100 1 3 ร 102 Grain of Rice (length) 0.006 6 thousandths 6 1,000 1 6 ร 1,000 6 ร 1 103 Human Hair (width) 0.00008 8hundred thousandths 8 100,000 8 ร 1 100,000 8 ร 1 105
For problems 13โ18, complete the table.
Ordering Numbers in Scientific Notation
19. Order the given numbers from least to greatest.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 197 LESSON
Number in Standard Form Number in Scientific Notation 13. 0.0007 14. 2 ร 10โ4 15. 2.3 ร 10โ4 16. 2.3 ร 10โ6 17. 0.000ย 0062 18. 3.018 ร 10โ5
3.6 7 ร 10โ2 3.2 ร 102 7.02 ร 104 6 ร 104 3 ร 102 4.6 ร 10โ2
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 14
Name
For problems 1 and 2, write the number in scientific notation.
1. 60,630,000
2. 0.0051
For problems 3 and 4, write the number in standard form.
3. 3 ร 10โ5
4. 3.4 ร 1010
5. Order the numbers from least to greatest.
Date
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 199
EXIT TICKET 14
6.0 ร 108, 9.2 ร 10โ15, 5.1 ร 109, 8.4 ร 109, 7.4 ร 10โ10, 6.8 ร 10โ15
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 14
Name Date
Writing Very Large and Very Small Numbers in Scientific Notation
In this lesson, we
โข defined scientific notation.
โข identified examples and nonexamples of numbers written in scientific notation.
โข wrote numbers in scientific notation and in standard form.
โข ordered numbers written in scientific notation.
Examples
Terminology
โข A number is written in scientific notation when it is represented as a numberย aย multiplied by a power of 10. Numbers written in scientific notation are in the form a ร 10n. The numberย a, which we call the first factor, is a number with an absolute value of at least 1 but less than 10
โข The order of magnitude n is the exponent on the power of 10 for a number written in scientific notation.
1. Circle all the numbers written in scientific notation. Numbers written in scientific notation must be in the form a ร 10n .
The absolute value of a, the first factor, must be at least 1 but less than 10
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 201
RECAP 14
9.82 ร 10 15 million 0.6 ร 1011 โ 6 ร 105 4.2 ร 10โ3 4,200,000
2. Complete the table.
The first nonzero digit is 3. The place value of the digit 3 is represented by 10โ8. The first factor is 3.2, which is at least 1 but less than 10
The power of 10, 10โ6, shows the place value of the first nonzero digit only, which is 2. The digits 0 and 9 are written after the decimal.
The first nonzero digit is 5. The place value of the digit 5 is represented by 10โ4, which is equal to 1 104 , or 1 10,000
7โ8 โธ M1 โธ TC โธ Lesson 14 EUREKA MATH2 ยฉ Great Minds PBC 202 RECAP
Number in Standard Form Number in Scientific Notation 0.0005 5 ร 10โ4 90,000 9 ร 104 0.000ย 0007 7 ร 10โ7 8,000 8 ร 103 0.000 002 09 2.09 ร 10โ6 0.000ย 000ย 032 3.2 ร 10โ8
3. The table shows the approximate weights of animals in pounds. Order the animals from heaviest to lightest.
Blue whale, African elephant, hippopotamus, giraffe, zebra, grizzly bear, colossal squid
The blue whale is the heaviest because its weight has the greatest order of magnitude, which is 5
The orders of magnitude are equal for the weights of the African elephant, the hippopotamus, and the giraffe.
In this case, use the first factor of each weight to determine the correct order.
9.5 > 6 > 2.2
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 203 RECAP
Animal Approximate Weight (pounds) African Elephant 9.5
Blue Whale 3.5
Colossal Squid 4.4
Giraffe 2.2
Grizzly Bear 8 ร
Hippopotamus 6 ร
Zebra 8.8 ร
ร 103
ร 105
ร 102
ร 103
102
103
102
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 14
PRACTICE 14
1. Circle all the numbers written in scientific notation.
2. Match each number written in standard form with its corresponding number written in scientific notation.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 205
Name Date
โ 9.99 ร 107 5.5 trillion 6.758 ร 10โ6 10 ร 103 1,570,000,000 โ 0.28 ร 102 8 ร 10 48.6 ร 10โ5
8,940 8.94 ร 103 8,940,000 8.94 ร 106 8,094 8.094 ร 103 890,400 8.904 ร 105 89,400 8.94 ร 104
For problems 3โ14, complete the table.
15. In 2014, the United States discarded a total of 5.08 ร 109 pounds of trash. Write this number in standard form.
16. Sara believes that the number 3 ร 10 is not written in scientific notation. Do you agree or disagree? Explain.
7โ8 โธ M1 โธ TC โธ Lesson 14 EUREKA MATH2 ยฉ Great Minds PBC 206 PRACTICE
Number in Standard Form Number in Scientific Notation 3. 3,000 4. 3 ร 10โ3 5. 2 ร 106 6. 575,000 7. 0.0006 8. 4.5ย ร 105 9. 0.00045 10. 0.000ย 007 11. 9.2 ร 10โ6 12. 0.00601 13. 5.505 ร 103 14. 8,095,000
17. In 2021, the richest person in the world had a net worth totaling about $177 billion. Write this number in scientific notation.
18. The mass of a neutron is about 1.67493 ร 10โ27ย kg. The mass of a proton is about 1.67262 ร 10โ27 kg. Explain which is heavier.
19. Before 2006, Pluto was considered to be one of the planets in our solar system. Many people thought it should be classified as a dwarf planet instead. The table lists planets in our solar system, the dwarf planet Pluto, and their approximate width in meters.
List the planets, including Pluto, from least to greatest based on their width.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 207 PRACTICE
Planet Approximate Width (meters) Mercury 4.88 ร 106 Venus 1.21 ร 107 Earth 1.28 ร 107 Mars 6.79 ร 106 Jupiter 1.43 ร 108 Saturn 1.2 ร 108 Uranus 5.11 ร 107 Neptune 4.95 ร 107 Pluto 2.4 ร 106
For problems 20โ23, multiply.
For problems 24โ26, apply the properties of exponents to write an equivalent expression. Assume y is nonzero.
7โ8 โธ M1 โธ TC โธ Lesson 14 EUREKA MATH2 ยฉ Great Minds PBC 208 PRACTICE Remember
20. โ 2 3 ( 7 10 ) 21. โ 2 5 (7 9 ) 22. โ 5 6 (โ 1 5 ) 23. 2 9 (โ 7 10 )
24.
25. (3 x 3)2 26. (__ 42 y )4
(84)3
27. Choose all the true number sentences.
A. 82 = 8 โ
8
B. 52 = 5 2
C. 42 = 8
D. 4 โ
4 โ
4 = 34
E. 7 โ
7 โ
7 = 73
28. Choose one false number sentence from problem 27. Explain why it is false.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 14 ยฉ Great Minds PBC 209 PRACTICE
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 15
Name Date
LESSON 15
Operations with Numbers Written in Scientific Notation
1. Liam enters 200,000 ร 450,000 into his calculator. The screen shows the following display.
a. Write 200,000 in scientific notation.
b. Write 450,000 in scientific notation.
Adding and Subtracting
2. The table shows the number of views for the following online videos.
a. How many total views do the singing cat video and the science experiment video receive? Write the answer in scientific notation.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 211
9e+ 10
Video Number of Views Singing cat 55,000,000 Science experiment 1.1 ร 107 Dancing baby 2 million Talking parrot 5.1 ร 107
b. How many more views does the singing cat video receive than the science experiment video? Write the answer in scientific notation.
c. How many more views does the singing cat video receive than the talking parrot video? Write the answer in scientific notation.
d. How many total views do the talking parrot video and the dancing baby video receive? Write the answer in scientific notation.
7โ8 โธ M1 โธ TC โธ Lesson 15 EUREKA MATH2 ยฉ Great Minds PBC 212 LESSON
e. How many more views does the science experiment video receive than the dancing baby video? Write the answer in scientific notation.
Multiplying and Dividing
3. The length of Colorado is about 611,551 meters. The width is about 450,616 meters.
a. Approximate the length and width of Colorado by rounding to the nearest hundred thousand meters. Then write the length and width in scientific notation.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 213 LESSON
Colorado
b. Approximate the area of Colorado. Write the answer in scientific notation.
c. The area of Denver, the capital of Colorado, is approximately 4 ร 108 square meters. The area of Colorado is about how many times as large as the area of Denver? Write the answer in scientific notation.
7โ8 โธ M1 โธ TC โธ Lesson 15 EUREKA MATH2 ยฉ Great Minds PBC 214 LESSON
Power to a Power
For problems 4 and 5, use the properties of exponents and the properties of operations to evaluate the expression. Write the answer in scientific notation. Check the answer with a calculator.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 215 LESSON
4. (8.85 ร 103)2
5. (2 ร 10โ9)3
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 15
Name
Date
1. After a series of calculations, a calculator screen displays this result.
4.399e14
Write the displayed value in scientific notation.
For problems 2โ4, evaluate the expression. Write the answer in scientific notation.
2. 1.3 ร 10โ4 + 2.1 ร 10โ4
3. 4.7 ร 105 โ 4.1 ร 105
4. (3 ร 10โ4)3
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 217
TICKET
EXIT
15
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 15
Name Date
Operations with Numbers Written in Scientific Notation
In this lesson, we
โข interpreted numbers displayed in scientific notation on digital devices.
โข used the properties and definitions of exponents and the properties of operations to efficiently operate with numbers written in scientific notation.
โข wrote sums, differences, products, and quotients in scientific notation.
Examples
1. A calculator displays 3.45eโ4. Write this number in scientific notation and in standard form. 3.45 ร 10โ4 = 0.000 345
For problems 2โ4, evaluate the expression. Write the answer in scientific notation.
2. 2.7 ร 10โ9 + 8.1 ร 10โ9
The addends have a common power of 10, 10โ9. So the distributive property can be applied.
2.7 ร 10โ9 + 8.1 ร 10โ9 = (2.7 + 8.1) ร 10โ9
= 10.8 ร 10โ9
= (1.08 ร 10) ร 10โ9 = 1.08 ร (10 ร 10โ9) = 1.08 ร 10โ8
The number 10.8 ร 10โ9 is not written in scientific notation because the absolute value of the first factor is greater than 10. Use the associative property of multiplication and the property xmxn = xm+n to write 10.8 ร 10โ9 in scientific notation.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 219 RECAP
15
3. (9 ร 10 โ7)(3.4 ร 10 2)
(9 ร 10โ7)(3.4 ร 102) = (9)(3.4) ร (10โ7)(102) Use the commutative and associative properties of multiplication to rewrite the original expression. Then multiply the factors in each pair.
= 30.6 ร 10โ5 = (3.06 ร 10) ร 10โ5 = 3.06 ร (10 ร 10โ5) = 3.06 ร 10โ4
4. (1.6 ร 10โ8)3 (1.6 ร 10โ8)3 = 1.63 ร (10โ8)3
Use the properties (xy)n=xnyn and (xm)n=xm โ
n to evaluate (1.6 ร 10โ8)3 = 4.096 ร 10โ24
5. Use the table of approximate animal weights to complete each part.
7โ8 โธ M1 โธ TC โธ Lesson 15 EUREKA MATH2 ยฉ Great Minds PBC 220 RECAP
Animal Approximate Weight (pounds) Aphid 4.4 ร 10โ7 Emperor scorpion 6.6 ร 10โ2 Gray tree frog 1.6 ร 10โ3 Termite 3.3 ร 10โ6
a. About how many more pounds does a gray tree frog weigh than an aphid?
(1.6 ร 10โ3) โ (4.4 ร 10โ7) = (1.6 ร 10โ3) โ (4.4 ร 10โ4 ร 10โ3)
To determine how many more pounds the gray tree frog weighs than the aphid, find the difference of their weights.
= (1.6 ร 10โ3) โ (0.00044 ร 10โ3) = (1.6 โ 0.00044) ร 10โ3
= 1.59956 ร 10โ3
Write 10โ7 as 10โ4 ร 10โ3 Then apply the distributive property.
Another strategy is to use 10โ7 as the common power of 10 1.6 ร 10โ3 can be written as 1.6 ร 104 ร 10โ7
A gray tree frog weighs about 1.59956 ร 10โ3 pounds more than an aphid.
b. An emperor scorpion is about how many times as heavy as a termite?
Divide the weight of the scorpion by the weight of the termite.
= 2 ร 104 = 20,000
An emperor scorpion is about 20,000 times as heavy as a termite.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 221 RECAP
3.3
6.6 3.3
6.6 ร 10โ2 = โ
(3.3 ร 10โ6) 6.6 ร 10โ2
ร 10โ6 = (
) ร 10โ2(10โ6 ) ________ ___ ____
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 15
Name
PRACTICE 15
Date
For problems 1โ4, write the answer displayed on the calculator screen in scientific notation and in standard form.
1. 5.678e+17
2. 0.0000023*0.0000 5 1.15ห -10
3. 1.386471e9
4. (1.39*109 )2 1.9321*1018
For problems 5โ14, evaluate the expression. Write the answer in scientific notation.
5. 4 ร 103 + 3 ร 103
6. 9 ร 10โ8 โ 2.7 ร 10โ8
7. (9 ร 1010)(1.1 ร 103)
8. 6 ร 10โ6 + 8 ร 10โ6
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 223
7โ8 โธ M1 โธ TC โธ Lesson 15 EUREKA MATH2 ยฉ Great Minds PBC 224 PRACTICE
5
105 + 3
104 10. (2.2 ร 104)(5.4 ร 107)
5.6
105 2 ร 10โ3 12. (2 ร 10โ3)4
9.
ร
ร
11.
ร
13. 9.6 ร 1010 โ 3 ร 1010 + 2.2 ร 1010 14. 9.8 ร 105 + 7.4 ร 105 + 8.9 ร 105
15. Use the table of approximate animal weights to complete each part. Check each answer with a calculator.
a. About how many more pounds does a hummingbird weigh than a monarch butterfly?
b. About how many more pounds does a wood mouse weigh than a monarch butterfly?
c. A wood mouse is about how many times as heavy as a monarch butterfly?
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 225 PRACTICE
Animal Approximate Weight (pounds) Giraffe 2.2 ร 103 Housefly 2.6 ร 10โ5 Hummingbird 8.8 ร 10โ3 Monarch butterfly 1.1 ร 10โ3 Wood mouse 4.4 ร 10โ2 Zebra 8.8 ร 102
d. About how many more pounds does a zebra weigh than a wood mouse?
e. Which animal or insect is about 8 times as heavy as a monarch butterfly?
f. A zebra is about how many times as heavy as a hummingbird?
7โ8 โธ M1 โธ TC โธ Lesson 15 EUREKA MATH2 ยฉ Great Minds PBC 226 PRACTICE
Remember For problems 16โ19, divide. 16. 3 รท 1 4 17. 1 4 รท 3 18. 6 รท ( 1 3 ) 19. 1 6 รท ( 3)
20. Eve and Lily each write an equivalent expression for x 7 x 3 . The table shows their work.
Eveโs Work Lilyโs Work
Explain how Eve and Lily each use the properties and definitions of exponents to get the final expression.
21. Which expression is equivalent to 5 6 โ
54?
A. 2524
B. 1010
C. 524
D. 510
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 15 ยฉ Great Minds PBC 227 PRACTICE
__ 7 x x 3 = x 7 โ
x โ3 = x 7+(โ3) = x 4 7 x x 3 = x 3 x 4 x 3 __ _____ = x 4
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 16 LESSON 16
Name Date
Applications with Numbers Written in Scientific Notation
Operating with Numbers in Scientific Notation
Comparing and Converting Units
How Many Times as Large and How Much Larger
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 16 ยฉ Great Minds PBC 229
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 16
Name
Date
A popular television series is added to your favorite online streaming service. It will take 1.902 ร 105 seconds to watch the entire series.
a. Choose a more appropriate unit of measurement to describe the amount of time needed to watch the entire series. Explain why you chose that unit.
b. Convert the unit from seconds to the unit of measurement you chose in part (a). Round your answer to the nearest tenth of a unit.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 16 ยฉ Great Minds PBC 231
EXIT TICKET 16
c. The entire series has 15 episodes for each of the 4 seasons. What is the approximate number of minutes per episode?
7โ8 โธ M1 โธ TC โธ Lesson 16 EUREKA MATH2 ยฉ Great Minds PBC 232 EXIT TICKET
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 16
Name
Date
Applications with Numbers Written in Scientific Notation
In this lesson, we
โข determined an appropriate unit of measurement for a given situation.
โข converted units of measurement to more appropriate units of measurement.
โข operated with numbers written in scientific notation.
Examples
1. A hawk can travel about 1.552 ร 107 inches per day.
a. Choose a more appropriate unit of measurement to describe the distance a hawk travels per day. Explain why you chose that unit.
A more appropriate unit of measurement is miles per day because it uses a larger unit for the distance, which makes the measurement simpler to interpret.
b. Convert the unit from inches per day to the unit of measurement you chose in part (a).
1 foot = 12 inches
1 mile = 5,280 feet
There are 12(5,280) , or 63,360 , inches in 1 mile. Divide 1.552 ร 107 inches by 63,360 inches to find how many miles the hawk can travel each day.
107
A hawk can travel about 2.4 ร 10 2 , or 240, miles per day.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 16 ยฉ Great Minds PBC 233
RECAP 16
12(5,280) 1.552
= 63,360
1.552 ร
ร 107
1.552 ร
= 6.336 ร
7 = (1.552 6.336 ) ร 10
104
โ 0.24 ร
= (2.4 ร
3 = 2.4 ร
= 2.4
107
104
(
)
103
10โ1) ร 10
(10โ1 ร 103)
ร 102
c. The longest distance around Earth is about 4 ร 104 kilometers. Using your answer from part (b), about how many weeks would it take for a hawk to travel that distance? Assume the hawk travels at a constant rate. (1 mile โ
kilometers)
A hawk travels about 384 kilometers per day.
It would take about 104 days. There are 7 days in 1 week.
It would take about 15 weeks for a hawk to travel the longest distance around Earth. Round 14.86 to the nearest whole number to determine the approximate number of weeks.
2. Water flows from a shower head at a rate of 7.57 ร 103 cubic centimeters per minute.
a. Determine the rate that water flows from the shower head in cubic meters per minute. There are 106 cubic centimeters in 1 cubic meter.
7.57 ร 103 106 = 7.57 ร 103(106 ) = 7.57 ร 10โ3
Water flows from the shower head at a rate of 7.57 ร 10โ3 cubic meters per minute.
Visualize a cube with an edge length of 1 meter, which is 100 centimeters.
The volume of the cube can be expressed as 1 cubic meter or 1,000,000 cubic centimeters.
1 cubic meter = 106 cubic centimeters
7โ8 โธ M1 โธ TC โธ Lesson 16 EUREKA MATH2 ยฉ Great Minds PBC 234 RECAP
240 โ
1.6 =
1.6
384
the
of
to
4 ร 104 384 = 4 ร 104 3.84 ร 102 Divide the longest distance around Earth by the distance traveled by the hawk per day. ___ 4 = (____ 4 3.84 ) ร 10(102 ) โ 1.04 ร 102 = 104
Convert
number
miles traveled in 1 day
kilometers.
104 7 โ 14.86
1 m 1 m 1 m 100 cm 100 cm 100 cm
b. Determine the rate that water flows from the shower head in cubic meters per second. There are seconds in minute. 60 1
7.57 ร 10โ3 60 = (7.57 60 ) ร 10โ3
โ 0.126 ร 10โ3
= (1.26 ร 10โ1) ร 10โ3 = 1.26 ร (10โ1 ร 10โ3)
= 1.26 ร 10โ4
Water flows from the shower head at a rate of about 1.26 ร 10โ4 cubic meters per second.
EUREKA MATH2 7โ8 โธ M1 โธ TC โธ Lesson 16 ยฉ Great Minds PBC 235 RECAP
Student Edition: Grade 7โ8, Module 1, Topic C, Lesson 16
Name Date
The Spiral of Theodorus
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 20 ยฉ Great Minds PBC 287 LESSON
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 20 โธ Spiral of Theodorus ยฉ Great Minds PBC 289 1 1 01234 Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 20
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 20
Name Date
1. Use square root notation to express the length of the hypotenuse c. Then approximate the length by stating the two consecutive whole number lengths the length of the hypotenuse is between. Explain how you know. c
For problems 2 and 3, evaluate.
4. Order the following numbers from least to greatest:
.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 20 ยฉ Great Minds PBC 291
EXIT TICKET 20
7
5
(โ9 )2 3. (โ3 )2
2.
, โ 8 , 1, โ 5 , 4, โ 2
3
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 20
Using the Pythagorean Theorem
In this lesson, we
โข used square root notation to express hypotenuse lengths that are not rational.
โข determined which two consecutive whole numbers the length of a hypotenuse is between.
โข found the squares of numbers written with square root notation.
โข created the Spiral of Theodorus to relate square roots to length measurements.
Terminology
A square root of a nonnegative number x is a number with a square that is x. The expression โx represents the positive square root of x when x is a positive number. If x is 0, then โ0 = 0
โข plotted points on a number line to represent locations of square roots.
Examples
1. Use square root notation to express the length of the hypotenuse c. Then approximate the length by stating the two consecutive whole number lengths the length of the hypotenuse is between. Explain how you know.
What number squared is 106? Use the square root symbol to represent the exact value.
This expression means the square root of 106
The number 106 is between 100 and 121. So the value of c is between 10 and 11 because 102 = 100 and 112 = 121
The length of the hypotenuse is โ106 units, which is between 10 units and 11 units.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 20 ยฉ Great Minds PBC 293
RECAP 20
Name Date
95 c a2 + b2 = c 2 52 + 92 = c 2 25 + 81 = c 2 106 = c 2 โ106 = c
2. Evaluate (โ70 )2 . 70
Because โ70 is the number with a square that is 70, then (โ70 )2 = 70
3. Use square root notation to express the length of the hypotenuse c. Then approximate the length by stating the two consecutive whole number lengths the length of the hypotenuse is between. Explain how you know.
The number 8 is between 4 and 9. So the value of c is between 2 and 3 because 22 = 4 and 32 = 9.
The length of the hypotenuse is โ8 units, which is between 2 units and 3 units.
7โ8 โธ M1 โธ TD โธ Lesson 20 EUREKA MATH2 ยฉ Great Minds PBC 294 RECAP
1 7 c โ 12 + (โ7 )2 = c 2 1 + 7 = c 2 8 = c 2 โ8 = c (โx )2 = x for any nonnegative number x
4. Which point represents the approximate location of โ12 on a number line? (โ12 )2 = 12, and 12 is between the two perfect squares 9 and 16 913
Because 32 = 9 and 42 = 16, the number squared to get 12 must be between 3 and 4
Point B represents the approximate location of โ12 on the number line.
The inequality 3 < โ12 < 4 indicates that โ12 is greater than and less than 4 3
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 20 ยฉ Great Minds PBC 295 RECAP
2345678101112 ABCDEF G 01
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 20
For problems 1 and 2, determine which two consecutive whole numbers the length of the hypotenuse c is between. 1.
For problems 3โ6, state whether the expression represents a whole number. If yes, state the whole number that is equal to the expression. If no, state the two consecutive whole numbers that the expression is between. 3.
For problems 7โ11, determine whether the statement is true or false.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 20 ยฉ Great Minds PBC 297
Date
PRACTICE 20 Name
c 610
c 5 5
2.
6. โ
โ16 4. โ40 5. โ125
144
7. (โ2 )2 = 2 8. (โ4 )2 = 16 9. (โ16 )2 = 4 10. 11 = (โ11 )2 11. โ81 = 32
For problems 12โ17, use square root notation to express the length of the hypotenuse. If the length is not a whole number, approximate the length by stating the two consecutive whole number lengths the length of the hypotenuse is between.
12. The leg lengths of a right triangle measure 1 unit and 3 units.
13. The leg lengths of a right triangle measure 4 units and 10 units.
1 unit and โ5 units.
18. Consider a right triangle with hypotenuse length c and leg lengths a and b. Is it possible for c 2 to be a perfect square when a2 and b2 are not perfect squares? If so, give an example.
7โ8 โธ M1 โธ TD โธ Lesson 20 EUREKA MATH2 298 PRACTICE
14. The leg lengths of a right triangle measure
16. 4 c 11
7 c 6
15. The leg lengths of a right triangle measure โ2 units and โ7 units.
17.
ยฉ Great Minds PBC
19. Which point represents the approximate location of โ8 on a number line? Write an inequality to describe the location of โ8 between two consecutive whole numbers on a number line.
20. Which numbers are between 3 and 4? Choose all that apply.
Remember
For problems 21โ24, divide.
For problems 25 and 26, state whether the number is a perfect square, a perfect cube, both, or neither. Explain how you know.
25. 110
26. โ8
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 20 ยฉ Great Minds PBC 299 PRACTICE
345678
012 BCDEFGA
A. โ2 B. โ4 C. โ10 D. โ12 E. โ15
21. 2 รท 2 1 2 22. โ6 รท 2 1 2 23. 8 รท (โ1 1 4 ) 24. โ5 รท (โ6 1 3 )
For problems 27 and 28, solve
27. x 2 = 64
29. While working on calculations for her science homework, Eve saw the following display on her calculator. 4.1633363e-
Write this number in scientific notation to help Eve interpret her calculatorโs display.
7โ8 โธ M1 โธ TD โธ Lesson 20 EUREKA MATH2 ยฉ Great Minds PBC 300 P RACTICE
28. k 2
1 81
=
17 Rad x! ( ) % AC Inv sin In 7 8 9 รท โ cos log 4 5 6 ๐ Rad Rad Rad Rad Rad Rad Rad e tan โ 1 2 3 โRad Rad Rad Rad Rad Rad Rad Ans EXP x y 0 = +
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 21 LESSON
Name Date
Approximating Values of Roots
Approximating Square Roots
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 21 ยฉ Great Minds PBC 301
21
Approximating Cube Roots
1. Write the cube root symbol.
2. Explain why the cube root symbol is needed to determine the edge length of the cube shown.
Volume: 18 cubic units
7โ8 โธ M1 โธ TD โธ Lesson 21 EUREKA MATH2 ยฉ Great Minds PBC 302 LESSON
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 21
Name Date
Approximate the value of โ17 to the nearest tenth by using consecutive whole numbers, tenths, and hundredths. Explain your thinking.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 21 ยฉ Great Minds PBC 303
EXIT TICKET 21
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 21
Approximating Values of Roots
In this lesson, we โข approximated values of square roots. โข explored and defined cube root notation and approximated the values of cube roots.
Examples
Terminology
The cube root of a number x is a number with a cube that is x. The
x expression represents the cube root of x.
For problems 1 and 2, determine the two consecutive whole numbers each value is between.
For problems 3 and 4, round each value to the nearest whole number.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 21 ยฉ Great Minds PBC 305
Name Date
RECAP 21
3 โ
1. 8 < โ68 <
68 is between the perfect squares 64 and 81 โ64 < โ68 < โ81 8 < โ68 < 9 2. 2 < 3 โ12 < 3 12 is between the perfect cubes 8 and 27 3 โ8 < 3 โ12 < 3 โ27 2 < 3 โ12 < 3
9
14 200
โ196 < โ
14 < โ
200
2
14.22
14.1
4. 3 โ53 4 53 is between the
and
3 โ27 < 3 โ53 < 3 โ64 3 < 3 โ53 < 4 53 is between 3.73 and 3.83, or 50.653 and 54.872. Both 3.7 and 3.8 round to 4.
3. โ200
is between the perfect squares 196 and 225
200 < โ225
200 < 15
is between 14.1
and
, or 198.81 and 201.64. Both
and 14.2 round to 14.
perfect cubes 27
64
5. Approximate the value of 3 โ46 to the nearest tenth. Explain your thinking. Because 46 is between the perfect cubes 27 and 64, the value of 3 โ46 is between 3 and 4.
Next, I consider the tenths from 3 to 4. I find that 46 is between 3.53 and 3.63, or 42.875 and 46.656.
Then, I consider the hundredths from 3.5 to 3.6. I find that 46 is between 3.583 and 3.593, or 45.882712 and 46.268279. Both 3.58 and 3.59 round to 3.6, so 3 โ46 โ 3.6.
7โ8 โธ M1 โธ TD โธ Lesson 21 EUREKA MATH2 ยฉ Great Minds PBC 306 RECAP
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 21
Name Date
For problems 1โ4, determine the two consecutive whole numbers each value is between.
1. < โ17 <
3. < โ6 <
2. < โ88 <
4. < โ 3 30 <
For problems 5โ8, round each value to the nearest whole number.
5. โ2
โ90 7. โ150
9. Henry states that the value of โ30 is between 5.5 and 5.6. Do you agree with Henry? Why?
10. Is the value of 3 โ25 greater than or less than 3? How do you know?
11. Approximate the value of โ23 to the nearest tenth. Explain your thinking.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 21 ยฉ Great Minds PBC 307
PRACTICE 21
8. โ 3 10
6.
For problems 12โ14, approximate the value by rounding to the nearest whole number, tenth, and hundredth.
15. Find the exact length of the hypotenuse c. Then approximate the length by rounding to the nearest tenth.
For problems 16โ19, divide.
7โ8 โธ M1 โธ TD โธ Lesson 21 EUREKA MATH2 ยฉ Great Minds PBC 308 PRACTICE
Root Whole Number Tenth Hundredth
12. โ57 13. โ119 14. โ 3 70
5 4 c Remember
16. 1 4 รท (โ1 3 5 ) 17. โ1 4 7 รท 1 5 18. 1 3 รท (โ2 1 3 ) 19. 4 1 6 รท 1 5
20. Find the length of the hypotenuse c.
21. The total volume of fresh water on Earth is approximately 3.5 ร 107 cubic kilometers. The total volume of all water on Earth is approximately 1.4 ร 109 cubic kilometers. What is the approximate volume of the water on Earth that is not fresh water? Write your answer in scientific notation.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 21 ยฉ Great Minds PBC 309 PRACTICE
12 c 5
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 22
Name Date
Rational and Irrational Numbers
LESSON 22
For problems 1โ6, identify the decimal digit that comes next in the decimal form of the number. If you cannot identify the next decimal digit, indicate that.
1. 1 = 0.333333333 3 โฆ
2. โ 3 12 = 2.2894284โฆ
3. 144 = 1.45454545 99
4. 3 5 = 3.41666666 12 โฆ
5. โ42 = 6.480740698โฆ
6. 3 = 0.428571428571 7 โฆ
Battle Cards
7. Plot and label the approximate location of each value on the number line.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 22 ยฉ Great Minds PBC 311
โ17 , โ 3 120 , _ 1 9 , โ 2 , โ 3 27 , โ27 0123456
Ordering Expressions
For problems 8 and 9, order the expressions from least to greatest. 8.
7โ8 โธ M1 โธ TD โธ Lesson 22 EUREKA MATH2 ยฉ Great Minds PBC 312 LESSON
โ28 , โ22 , โ28 โ 5, โ22
โ17 โ 2, 2 โ
โ17 , โ17 + 2
+ 5 9.
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 22
1. Indicate whether each number is rational or irrational.
10โ3
2. Compare the values by using the < or > symbol. Explain your reasoning.
3. Plot and label a point at the approximate location of each value on the number line.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 22 ยฉ Great Minds PBC 313 Name Date
Number Rational Irrational 4 5 โ81 0.20406081โฆ 2.134 ร
0.3 3 โ 9
โ27 3 โ 40
โ24 , 4.2 3, โ16 , 14 3 , 3 โ 125 4 4.5 5 EXIT TICKET 22
Name Date
Rational and Irrational Numbers
In this lesson, we
โข identified real numbers as rational or irrational.
โข compared and ordered rational and irrational numbers.
โข plotted the approximate locations of rational and irrational numbers on a number line.
Examples
Terminology
An irrational number is a number that is not rational and cannot be expressed as p q for integer p and nonzero integer q. An irrational number has a decimal form that neither terminates nor repeats.
A real number is any number that is either rational or irrational.
For problems 1โ4, identify whether the number is rational or irrational.
1. 4 3 Rational A rational number can be written as a fraction.
2. โ0.24680153โฆ
Irrational
When the decimal form of a number neither terminates nor repeats, the number cannot be written as a fraction and is irrational.
Negative numbers can be rational or irrational.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 22 ยฉ Great Minds PBC 315 RECAP 22
โ3 Irrational
3 โ 8 = 2 4. โ โ 3 8 Rational
3.
Roots can be rational or irrational. โโ3 = โ1.73205โฆ
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 22
For problems 5โ8, compare the values of the expressions by using the < or > symbol.
5. 3.94 < 3 โ65
Because 3 โ 64 = 4, 3 โ 65 is greater than 4. So 3. 94 is less than 3 โ 65
15
Because 3 โ 64 = 4, and 3 โ125 = 5, 3 โ120 is between 4 and 5.
Because โ9 = 3 and โ16 = 4, โ15 is between 3 and 4.
Because โ49 = 7, โ50 is greater than 7
โ50 > 62 9 7.
Because 63 9 = 7, 62 9 is less than 7
The value of 3 โ 25 is between 2 and 3. Adding 4 to 3 โ 25 gives a number that is between 6 and 7. Multiplying 3 โ 25 by 2 gives a number that is between 4 and 6
9. Plot and label a point at the approximate location of each value on the number line.
17
Because 3 โ 27 = 3 and 3 โ 64 = 4, 3 โ 30 is between 3 and 4
Because โ16 = 4 and โ25 = 5, โ17 is between 4 and 5
7โ8 โธ M1 โธ TD โธ Lesson 22 EUREKA MATH2 ยฉ Great Minds PBC 316 RECAP
6.
3 โ120 > โ
8. 3 โ25 + 4 > 2 ยท 3 โ25
8 3 , 3 โ30 , 2.4
โ
5 1 2 3 4 0 8 3 2. โ4 โ30 3 17โ
,
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 22
PRACTICE 22
1. Write each value in the appropriate column of the table.
Rational
Irrational
2. Abdul can predict the next decimal digit in the number 0.010305070โฆ , so he concludes that the number is rational. Explain the error in Abdulโs thinking.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 22 ยฉ Great Minds PBC 317
Name Date
โ 3 5 2 โ 3 115 โ 3 64 0 โ โ18 0.23742374โฆ โ25 0.67534702โฆ โ 5.67
3. Ethan states that โ5 is an irrational number. Nora states that โ5 is a real number. Who is correct? Explain.
For problems 4โ9, compare the values by using the < or > symbol.
7โ8 โธ M1 โธ TD โธ Lesson 22 EUREKA MATH2 ยฉ Great Minds PBC 318 PRACTICE
4. โ49 7. 1 5. โ20 โ 3 20 6. โ 3 27 โ15 7. โ 3 64 37 9 8. โ121 87 8 9. 34 7 โ 3 125
For problems 10 and 11, plot and label a point at the approximate location of each value on the number line.
12. Order the expressions from least to greatest.
Remember
For problems 13โ16, divide.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 22 ยฉ Great Minds PBC 319 PRACTICE
10. โ27 , โ 3 27 , โ11 , โ20 , โ 3 15 , โ4 23 4 5 6 11. 4.16, 40 7 , โ40 , โ90 โ 1, โ 3 120 , โ 3 3 + 6 4 5 6 7 8 9
โ8 , โ5 + 2, โ10 โ 3
13. โ 1 2 5 รท 1 1 2 14. โ 2 1 4 รท (โ 1 1 8 ) 15. 4 4 5 รท 1 1 5 16. 8 1 3 รท (โ 2 1 4 )
For problems 17 and 18, evaluate.
17. (โ25 ) 2
19. Order the numbers from least to greatest.
For problems 20 and 21, solve.
20. g 6 = 8
21. 40 = 3n
7โ8 โธ M1 โธ TD โธ Lesson 22 EUREKA MATH2 ยฉ Great Minds PBC 320 PRACTICE
18. (โ30 ) 2
4, โ17 , โ12 , 3, โ8
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 23 LESSON
Name Date
Revisiting Equations with Squares and Cubes
1. Indicate whether each equation has one solution, two solutions, or no solution.
Equation
x 2 = 0
x 2 = 1
x 2 = โ1
x 3 = โ1
x 3 = 8
x 2 = 8
Revisiting Equations of the Form x
2
= p
For problems 2โ5, solve the equation. Identify the solutions as rational or irrational.
2. x 2 = 25
3. x 2 = 8
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 23 ยฉ Great Minds PBC 321
23
One Solution Two Solutions No Solution
Revisiting Equations of the Form x 3 = p
For problems 6โ9, solve the equation. Identify all solutions as rational or irrational. 6.
7โ8 โธ M1 โธ TD โธ Lesson 23 EUREKA MATH2 ยฉ Great Minds PBC 322 LESSON 4. 49 = h2 4 5. t 2 = 0.01
t 3 = 27
โ25 = w 3
1 = w 3 8
38 = z 3
7.
8.
9.
10. Dylan solves the equation x 3 = โ64 but makes some errors. His work is shown. Help Dylan correct his work. x
The solutions are โ8 and 8
The Baseball Bat Problem
11. Lily wants to ship a baseball bat that is 32 inches long. She can buy a box that measures 20 inches by 20 inches by 20 inches. Will the baseball bat fit in the box? Explain your reasoning.
20inches
20inches
20inches
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 23 ยฉ Great Minds PBC 323 LESSON
3
x = โ 3 โ64 x =
or x = โ โ 3
x
= โ64
โ8
โ64
= โ(โ8) x = 8
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 23
Name Date
For problems 1โ3, solve the equation. Identify all solutions as rational or irrational.
1. x 2 = 13
2. x 3 = 36
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 23 ยฉ Great Minds PBC 325 EXIT TICKET
23
3. x 3 = 8 27
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 23
Name
Date
Revisiting Equations with Squares and Cubes
In this lesson, we
โข solved equations of the forms x 2 = p and x 3 = p.
โข expressed irrational solutions by using square root and cube root notation.
Examples
For problems 1 and 2, solve the equation. Identify all solutions as rational or irrational.
1. m2 = 35
m2 = 35
m = โ35 or m = โโ35
The solutions are โ35 and โโ35
Irrational
There are two numbers that equal a positive number when squared: a positive number and its opposite. So the equation has two solutions.
2. โ100 = r 3
The solution is 3 โโ100 .
Irrational
Notice that the variable is cubed. Although 100 is a perfect square, 100 and โ100 are not perfect cubes. โ 3 โ100 = r
โ100 = r 3
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 23 ยฉ Great Minds PBC 327
23
RECAP
3. A square has an area of 46 square centimeters. What is the side length of the square?
Let s represent the side length of the square in centimeters.
s2 = 46
s = โ46
The side length of the square is โ46 centimeters.
The area of a square can be found by squaring the side length. The side length of a square cannot be negative, so the positive solution is the only answer to the problem.
4. A cube has a volume of 12 cubic inches. What is the edge length of the cube?
Let x represent the edge length of the cube in inches.
x 3 = 12
x = โ 3 12
The edge length of the cube is โ 3 12 inches.
The volume of a cube can be found by cubing the edge length.
7โ8 โธ M1 โธ TD โธ Lesson 23 EUREKA MATH2 ยฉ Great Minds PBC 328 RECAP
Student Edition: Grade 7โ8, Module 1, Topic D, Lesson 23
1. Which numbers are solutions to the equation x 3 = 27? Choose all that apply.
2. The number โ1 is a solution to which equations? Choose all that apply.
For problems 3โ10, solve the equation. Identify all solutions as rational or irrational.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 23 ยฉ Great Minds PBC 329
Name Date
PRACTICE 23
A. 3 B. โ3 C. 3 โ โ27 D. โ 3 27 E. โ27 F. โโ27
A. x 2 = 0 B. x 2 = 1
x 2 = โ1 D. x 3 = 1
x 3 = โ1
C.
E.
3. y 2 = 27 4. m3 = 15 5. 200 = j2 6. n3 = โ1
11. In the equations, n, m, p, and q are positive numbers. Order n, m, p, and q from least to greatest.
15
30
12. A cube has a volume of 58 cubic centimeters. What is the edge length of the cube?
7โ8 โธ M1 โธ TD โธ Lesson 23 EUREKA MATH2 ยฉ Great Minds PBC 330 PRACTICE 7. h2 = 8 8. t 2 = 49 64 9. 1 8 = t 3 10. b2 = 100
n2 =
m3 =
p3 = 25 q2 = 20
13. A square has an area of 32 square inches. A cube has a volume of 120 cubic inches. Which is greater, the side length of the square or the edge length of the cube? Explain.
Remember
For problems 14โ17, evaluate.
18. Approximate the value of โ21 to the nearest tenth by using consecutive whole numbers, tenths, and hundredths. Explain your thinking.
EUREKA MATH2 7โ8 โธ M1 โธ TD โธ Lesson 23 ยฉ Great Minds PBC 331 PRACTICE
14. 3 4 + 2 5 15. ( 3 4 )( 2 5 ) 16. 5 8 2 5 17. 5 8 รท 2 5
19. Ava solves the equation 1 2 x = 26 but makes an error.
a. Identify Avaโs error. Explain what she should have done.
b. Show the correct work to solve the equation.
7โ8 โธ M1 โธ TD โธ Lesson 23 EUREKA MATH2 ยฉ Great Minds PBC 332 PRACTICE
1 2 x = 26 2(1 2 x) = 1 2 (26) x = 13
Student Edition: Grade 7โ8, Module 1, Mixed Practice 1