SHAPES

Basic knowledge

Type of triangle

Features eatures An equilateral

Equilateral triangle

Label

triangle side(edge)

sides

has all of its

of

the

same

length. And, three angles are

vertex

angle

Example2 Example1

Right angle

same size and equal to Example1

60째.

rotated

An isosceles

Isosceles triangle

triangle

has a pair of

sides of same length and a pair of vertices of Example1 Right angle = 90째

Parallel

Example2

Example1

same angles

rotated

An rightright-angled

Right-angled triangle

triangle

a

has

one

vertex angle equal to

b

90째

Line a is parallel to Example1

line b Example2

Example1

Perpendicular

rotated

A Scalene

Scalene triangle

triangle has all of

a

their length of the different length.

b Line a is perpendicular to line b Example1

Example2

Identical marking Same length

A rightright-angled

Combined feature

isosceles triangle Right-angled

Right-angled scalene isosceles triangle triangle Same angle

1

A rightright-angled scalene triangle

Type of quadrilaterals

Features eatures An trapezium

Trapezium

has only one

pair of parallel sides

1 pair of parallel arallel sides Example1

Example2

Example1

rotated

A parallelogram parallelogram pair of parallel sides.

Rhombus

Parallelogram

has two

Usually, one pair of sides is longer than the other pair. 2 pair of parallel sides

A rhombus

has all of its

length of the same length. 2

pair

of

Same length

length No right angle

And,

usually

parallelograms

and rhombus, both of them have

No right angle

no right angle.

A rectangle

has all of their

angles of right angles.

Rectangle

Square

Usually, one pair of sides is longer than other pair.

Right angle

Right angle

A square

has all of their

angles of right angles 2 pair of

Same length

Its sides are all the same same length

length

The

arrowhead

Arrowhead

Kite

kite

and

the

have two pair of

adjacent sides of same length

An arrowhead

has

one

interior vertex which is bigger than 180 degrees

symmetry

Over 180째 180째

symmetry A kite has which degrees

2

is

no interior vertex

bigger

than

180

Type of quadrilaterals quadrilaterals

Feature A trapezoid

Trapezoid

edges

Exercise Ex1) Ex1) Label triangles below a

b

c

d

Ex2) Draw identical markings at the angles(corners) angles(corners) a

b

c

Ex3) Draw identical markings at the sides a

d

c

b

Ex4) Label quadrilaterals quadrilaterals below. And explain difference of two quadrilaterals. quadrilaterals. a

b

3

e

has no parallel

Ex5) Look at the investigation below and answer the questions Quadrilateral A

Quadrilateral B

Investigation A

Investigation A

Investigation

Parallel sides

Parallel sides

Parallel sides

Parallel sides

B

Investigation B

Measure sides

Measure sides

3.5cm

5cm 3.5cm

3.5cm

3.5cm

3.5cm

3.5cm

5cm

4

Ex5Ex5-a) What can you identify in Investigation A ? choose correct one A. Both of quadrilaterals have two pair of parallel sides. B. Both of quadrilaterals have all of their side of same length C, Only one of them has two pair of parallel sides. Ex5Ex5-b) Which quadrilateral has all the same same length of sides Ex5Ex5-c) Write the name of two quadrilaterals

Ex6) Compare and Explain common feature and difference

Arrowhead

Kite

symmetry

symmetry Over 180째 180째

Hint 1. What is the difference of Kite and Arrowhead? 2. Only Rhombus has

5

Rhombus

Same length Symmetry