Question

1. Find the missing angle for each triangle.

2. Which triangles are similar (Hint: Angle-Angle Criterion)?

Answer 1

1: 42-degrees, 69-degrees, 64-degrees, 53-degrees

2: first triangle and last triangle are similar while the other two are similar to each other

Explanation:

1: 85 + 53 + x= = 180

138 + x = 180

x = 42

2: 47 + 64 + x = 180

111 + x = 180

x = 69

3: 47 + 69 + x = 180

116 + x = 180

x = 64

4: 85 + 42 + x = 180

127 + x = 180

x = 53