怎么解二元一次方程组2(x-y)/3-x+y/4=-1和6(x+y)-4(2x-y)=16

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怎么解二元一次方程组2(x-y)/3-x+y/4=-1和6(x+y)-4(2x-y)=16

怎么解二元一次方程组2(x-y)/3-x+y/4=-1和6(x+y)-4(2x-y)=16
怎么解二元一次方程组2(x-y)/3-x+y/4=-1和6(x+y)-4(2x-y)=16

怎么解二元一次方程组2(x-y)/3-x+y/4=-1和6(x+y)-4(2x-y)=16
2(x-y)/3-(x+y)/4=-1
6(x+y)-4(2x-y)=16
8(x-y)-3(x+y)=-12
3(x+y)-2(2x-y)=8,3x+3y-4x+2y=8,5y-x=8,y=(x+8)/5.
2x-3y=-2,x=1.5y-1.y=(1.5y+7)/5=0.3y+1.4,0.7y=1.4,y=2; x=2.
y=2; x=2.

擦,以前学的全忘完了。算到15y*y+60y-32=0就不会了