PLEASE HELP:
Rectangle FGHJ has diagonals FH and JG that intersect at M. If FJ=−3x+5y, FM=3x+y, GH=11, and GM=13, find the values of x and y.
A. x=3, y=4

B. x=7, y=8

C. x=4, y=3

D. x=8, y=7