2(x-y)/3 - x+y/4=-1 (1) 6(x+y)-4(2x-y)=16 (2) 解: (1)方程两边同乘以12得 8(x-y)-3(x+y)=-12 合并同类项得 5x-11y+12=0 (3) (2)合并同类项得 10y-2x-16=0 (4) (3)*2+(4)*5得 28y-56=0 所以 y=2 把y=2代入(1)得 x=2
x=4/5, y =44/25