2 (3-x) — (8+x) -4 (y+5)+(12-y) — (7-x)+4 (x-5) -9 (y-4) —

2 (3-x) — (8+x)=2*3+2*(-x)+(-1)*8+(-1)*x=6-2x-8-x=-2-3x-4 (y+5)+(12-y)=-4*y+(-4)*5+12-y=4y-20+12-y=3y-8- (7-x)+4 (x-5)=-1*7+(-1)*(-x)+4*x+4*(-5)=-7+x+4x-20=-13+5x-9 (y-4) — (12+y)=-9*y+(-9)*(-4)+(-12)+(-y)=-9y+36-12-y=-10y+24