Answer:
x = 10
m<A = 132 degrees
m<B = 48 degrees
Explanation:
Supplementary = angles that make up 180 degrees
We know <A and <B are supplemntary, so 2x+28+6x+72 = 180.
8x + 100 = 180
8x = 80
x = 10
I input 10 into the equations to solve for the measures of the angles