1. Interior Angles of Triangles
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Interior Angles of Triangles

2. Interior Angles of Triangles
12 November 2018
Interior Angles of Triangles

3. Investigating the total angles in a triangle

10. The angles in a triangle add up to 180°.

11. Clean Up Time!

12. Whiteboards

13. The angles in a triangle add up to 180°.
What is the size of angle A? A°
60°
The angles in a triangle add up to 180°.
60°
60°
60° + 60 ° = 120 °
180° - 120° = 60°

14. The angles in a triangle add up to 180°.
What is the size of angle A?
80° + 70 ° = 150 °
180° - 150° = 30° A
The angles in a triangle add up to 180°.
30°
80°
70°

15. What is the size of angle A?
80° + 40 ° = 120 °
180° - 120° = 60°
40° A
80°
60°

16. Complete the Sorting Activity
1st as class
2nd by them then with whole class
QUICK AFL before worksheets
Proper AfL after worksheets
Extension with interior/ exterior

17. Calculate the missing angle! Calculate the missing angle!

18. Calculate the missing angle!
90°
75°
50°
40°
60°
61°
40°
70°
13°
53°

19. EXTENSION:
Find the red angle.
120° ?° ?°
70°
80°
50°
120° ?°

20. EXTENSION:
Find the red angle.
120°
60°
130°
70°
80°
50°
120°
50°

21. Whiteboards

22. What is the size of angle A?
Whiteboards
50°
50° A
80°

23. What is the size of angle A?
Whiteboards
85°
65° A
30°

24. What is the size of angle A?
Whiteboards A
60°
75°
45°

25. What is the size of angle A?
Whiteboards
80°
55°
45° A