NB :
1. Adjacent angles on a straight line are equal to 180°
2. Vertically opposite angles are equal to each other
3. Corresponding angles are equal
4. Interior angles of a triangle add up to 180°
Explanation:
9. If A = 65°
B = 115°
C = 65°
D = 115°
E = 65°
F = 25°
10. If A = 70°
B = 110°
C = 70°
D = 110°
E = 70°
F = 20°
11. If F = 22°
A = 68°
B = 112°
C = 68°
D = 112°
E = 68°
12. If D = 116°
A = 64°
B = 116°
C = 64°
E = 64°
F = 26°