1. L.O. I can calculate the angles in a triangle.
Numeracy
L.O. I can calculate the angles in a triangle.

2. Types of Angle Right angle Acute angle Obtuse angle 90° Less than 90°
More than 90°
Straight angle
180°
Reflex angle
More than 180°

3. The angles in EVERY triangle add up to 180°
Angles in a triangle
The angles in EVERY triangle add up to 180°

4. What’s my angle? 60º 90º What’s this angle? 90° + 60° = 150°
180° - 150° = 30°

5. What’s my angle? 55º What’s this angle? 90° + 55° = 145°
180° - 145° = 35°

6. What’s my angle? 78º 30º What’s this angle? 78° + 30° = 108°
180° - 108° = 72°

7. What’s my angle? 60º What’s this angle? 60° + 60° = 120°
180° - 120° = 60°

8. What’s my angle? 80º 130º ? 50º What’s this angle? 50° + 80° = 130°
180° - 130° = 50°
180° - 130° = 50°

9. What’s my angle? 80º 115º 65º ? What’s this angle? 180° - 115° = 65°
50° + 80° = 130°
180° - 130° = 50°

10. L.O. I can calculate the angles in a triangle.
Orange Group:
Mrs Broughton will be working with you.
Working in pairs, draw triangles for each other. For each triangle:
a) Estimate the sizes of all three angles.
b) Measure two angles and check them together.
c) Calculate the third angle in the triangle using the 180° rule.
Yellow/Green Group:
Mrs Lowe will be working with you.
Complete page 54 of the Abacus book.
When you have finished, work in pairs to create your own triangle problems for each other and solve them.
Red/Blue Group:
Miss Rostron will be working with you.
Complete page 55 of the Abacus book.