{2x-4y/5=4x=64/5
{x+y/4=-4x-12/2

{2x/1-4y/5=4x/1=64/5*5{x/1+y/4=-4x/1-12/2*4{10x-4y=20x=64{4x+y=-16x-24{-10x-4y=64{20x+y=-24*4+{-10x-4y=64+{80x+4y=-9670x=-32:70x=-32/70=-16/3520*(-16/35)+y=-24-320/35+y=-24y=-24+9 5/35y=-14 30/35=-14 6/7