Question

Find the measure of a

Answer 1

C. 70°

Explanation:

but c = 180° - (2×20°) = 140°

b = 180° - c

b = 180° - 140° = 40°

`{ \sf{a = (1)/(2)c }} \\ { \sf{a = ( (1)/(2) * 140 \degree)}} \\ { \sf{a = 70 \degree}}`