Question

Find the measure of angle A.
80°
10x - 5
10x + 5

Answer 1

45° or 55° {you didn't say which one is A}

Explanation:

10x - 5° + 10x + 5° + 80° = 180°

20x = 100°

x = 5°

10x - 5° = 10×5° - 5° = 45°

10x + 5° = 10×5° + 5° = 55°