已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y

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已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y
已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y

已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y
2x-y/x+3y=2得
x+3y/2x-y=1/2
4x-2y/x+3y减4x+12y除以2x-y
=2(2x-y)/x+3y-4(x+3y)/2x-y
=2乘以2-4乖以1/2
=4-2
=2

应该是:已知(2x-y)/(x+3y)=2,求代数式(4x-2y)/(x+3y)减4x+12y除以2x-y
由(2x-y)/(x+3y)=2可得 y=0, x不为0,
(4x-2y)/(x+3y)=4x/x=4
4x+12y除以2x-y=4x/2x=2
即代数式4x-2y/x+3y减4x+12y除以2x-y=4-2=2

4x-2y/x+3y-4x+12y/2x-y
=2(2x-y)/ x+3y-4(x+3y)/2x-y
因为2x-y/x+3y=2,所以x+3y/2x-y=1/2
=2*2-4* 1/2
=4-2
=2