Answer:
x=12 ; y=8
Explanation:
8x+13=11x-23(2 opposite side of a parallelogram is equal)
move the x terms to the left side.
8x-11x=-23-13
-3x=-36
3x=36
x=12
2y+12=4y-4(2 opposite side of a parallelogram is equal)
move the y terms to the left side
2y-4y=-4-12
-2y=-16
2y=16
y=8