What is the measure of cº?
A. 7.5°
B. 15
C. 30°
D. 45

Answer:
x = 15
Step-by-step explanation:
The sum of the angles in a triangle is 180º
3x + 5x + 4x = 180
Combine like terms
12x = 180
Divide both sides by 12
x = 15
C = 5x
C = 5 * 15
C = 75º