2/3 x-3/4 y=1/2,左右各乘12得8x-9y=6----(1)
4(x-y)-3(2x+3y)=4x-4y-6x-9y=-2x-13y=17,2x+13y=-17----(2)
(2)*4-(1),可得61y=-74,y=-74/61,x=-75/122.验证正确