Quadrilateral ABCD is inscribed in this circle. What is the measure of angle A? Show your work.

Answer:
88°
Step-by-step explanation:
Angles B and D are supplementary, so the value of x is ...
x = 180° -116° = 64°
Then the measure of angle A is ...
(2x -40)° = (2·64 -40)° = 88°
The measure of angle A is 88°.