Question

ZA and ZB are vertical angles with mZA= x and mZB = 5x – 80. What is mA? Enter your answer in the box.​

Answer 1

20

Explanation:

vertical angles are equal. meas. of angle a = meas. of angle b

x=5x-80

x+80=5x

80=4x

20=x

Answer 2

A = 80

Explanation:

If they are vertical angles, they are equal.

5x - 80 = x Add 80 to both sides

5x - 80 + 80 = x + 80

5x = x + 80 Subtract x from both sides

5x - x = x - x + 80

4x = 80 Divide by 4

4x/4 = 80/4

x = 20