Question

What is the measures of angle ECD? Please show work.

Answer 1

The answer is D. 80°. Angle B is 60 because the angle is adjacent. That makes 60 the vertical angle for the second angle in the triangle with the 40. Since we know two of the angles, we add them together to get 100. 180-100 is 80°

Answer 2

The anser is 40

the resense is verticle angle are congrounent.