Question

10. What is the measure of angle C?
A. 25°
B. 30°
C. 60°
D. 75°

Answer 1

D

Explanation:

x + 5 + 3x + C = 180 All triangles have 180 degrees.

4x + 5 + C = 180

But C must be equal to 3x. Notice the markings on the lets of the triangle.

4x + 5 + 3x = 180

7x + 5 = 180 Subtract 5 from both sides

7x = 180 - 5

7x = 175

x = 25

But angle C = 3x

C = 3*25

C = 75