(1)3分之2(x-y)-4分之x+y=-1(通分,整理)得(3)
2(x-y)/3-(x+y)/4=-1
8(x-y)-3(x+y)=-12
8x-8y-3x-3y=-12
(3)5x-11y=-12
(2) 6(x+y)-4(2x-y)=16(整理)得(4)
3(x+y)-2(2x-y)=8
3x+3y-4x+2y=8
-x+5y=8(两边×5)
(4)-5x+25y=40与(3)相加
(3)5x-11y=-12
14y=28
y=2代入到-x+5y=8中
-x=8-5y
-x=8-5*2=-2
x=2