Question

In a triangle ABC, the measure of angle B is 5 times the measure of angle A, and the

measure of angle C is 5° less than 4 times the measure of angle A.
Find the measure of the angles.

Answer 1

B = 5A.
C = 4A - 5.
180 = A + B + C.

Solve by representing B and C in terms of A.
180 = A + 5A + 4A - 5
185 = 10A
A = 18.5 degrees.

Use A to find B and C
B = 5(18.5) = 92.5
C = 4(18.5) - 5 = 69

18.5 + 92.5 + 69 = 180

A = 18.5
B = 92.5
C = 69