Step-by-step explanation:
let's Recall the properties of a parallelogram
1. the opposite sides of a parallelogram is congruent
AB=CD
8x-7=5x+2
8x-5x=7+2
3x=9
x=3
2. the consecutive angles are supplementary
angle A+angle D=180°
2y+50°+3y+40°=180°
5y+90°=180°
5y=90°
y=18
