Question

In parallelogram ABCD , ∠A and ∠B are adjacent. The measure of ∠B is two times the measure of ∠A . Which equation gives the exact measure of ∠A ?

Answer 1

A = 2 * B - 30
in a parallelogram, opposite angles are equal.
sum of the angles in a parallelogram is 360 degrees.
this means that 2A + 2B = 360.
divide both sides of this equation by 2 to get:
A + B = 180.