Question

How do I do the math here? I am not sure how to set it up with having only one angle to work with.

Answer 1

angle A = 112 degrees

Explanation:

Angle ADC is bisected (given) ...so angle 1 = angle 2

then angle D = 68 degrees

now you have to remember that adjacent corners (angles on the same LEG) of a trapezoid sum to 180 (they are 'supplementary' )

angle A = 180 - 68 = 112 degrees