Curriculum for Excellence Maths and Numeracy Experiences and Outcomes Fourth Level MTH 4-17a Having investigated the relationship between a radius and a tangent and explored the size of the angle in a semi-circle, I can use the facts I have established to solve related problems. Links to current 5-14 Planners

Key Learning Intentions

Learnersâ&#x20AC;&#x2122; Experiences / Possible Contexts Consider: collaborative learning, creativity, problem solving/investigative approaches, use of ICT, links across the curriculum etc.

A tangent to a circle is a line which touches the circle exactly once on its circumference.

Key Vocabulary: Tangent, circle, circumference, radius, right angle, right-angled triangle, diameter, semi-circle.

A tangent to a circle meets its radius at right angles.

http://www.bbc.co.uk/scotland/learning/bitesize/standard/maths_i/meas ure/circle_angles_rev1.shtml

Using the radius and tangent as 2 sides, we can draw a third side from the centre of the circle to one end of the tangent to create a right-angled triangle.

I can identify and draw a tangent to a circle. I can identify the right angle where a tangent meets a radius. I can create a rightangled triangle using a radius, tangent and another line.

Using the diameter as the base, we can create a triangle in a semicircle by joining the ends of the diameter to one point on the circumference.

I can create a triangle within a semi-circle.

The triangle created in a semi-circle is always a right angled triangle; Angle, Symmetry and Transformation

Success Criteria

I can label the right angle in a triangle 1

City of Edinburgh Council

Evaluation and Next Steps

Curriculum for Excellence Maths and Numeracy Experiences and Outcomes the right angle being at the point on the circumference. We can use the fact that angles in a triangle add up to 180Ë&#x161; to find a missing angle in any triangle.

Angle, Symmetry and Transformation

in a semi-circle.

I can find a missing angle in a triangle.

2

City of Edinburgh Council

Angle, Symmetry and Transformation MTH 4-17a

A tangent to a circle meets its radius at right angles. I can create a right- angled triangle using a radius, tangent and another line. I ca...