Question

∠A and B∠ are vertical angles. If m∠A = (3x+9) and m∠B=(4x-7) , then find the measure of angle B∠.

Answer 1

57 degrees

Explanation:

vertical angles are equal. thus, 3x+9 = 4x-7

subtract 3x from both sides to put all x values and their coefficients on one side

9 = x-7

add 7 to both sides to isolate x

x = 16

B = 4x-7 = 4 * 16 - 7 = 57