GMy GYM MathMOE-aligned Primary Maths
Sign in
← Revision WorldP5
P5 · Topic

Angles & Shapes

Use angle facts: 180° in a triangle, 360° at a point.

Big Idea
Use angle facts: 180° in a triangle, 360° at a point.
a°a° + b° = 180°
Angles on a straight line make 180°.
Key points
  1. 1Angles in a triangle add to 180°.
  2. 2Angles on a straight line add to 180°.
  3. 3Angles at a point add to 360°.
  4. 4In an isosceles triangle, base angles are equal.
Worked example
  1. 1Sum of angles = 180°.
  2. 248° + 67° = 115°.
  3. 3Third = 180° − 115° = 65°.
Answer: 65°
GYM Teaching Tip
Label every angle you know before solving. Write the rule beside it.
See the question behind this example
Two angles of a triangle are 48° and 67°. Find the third angle.