(3x+2y)/2=(2x+y)/3=(x-y+1)/4=r 3x+2y=2r (1) 2x+y=3r (2) x-y+1=4r (3) (1)*2 6x+4y=4r (4) (4)-(3) 5x+5y=1 (1)*3-(2)*2 5x+4y=0 y=1 x=-4/5
