数学题:已知x+3xy-y=0,求代数式2x-14xy-2y/x-2xy-y的值.

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数学题:已知x+3xy-y=0,求代数式2x-14xy-2y/x-2xy-y的值.
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数学题:已知x+3xy-y=0,求代数式2x-14xy-2y/x-2xy-y的值.
数学题:已知x+3xy-y=0,求代数式2x-14xy-2y/x-2xy-y的值.

数学题:已知x+3xy-y=0,求代数式2x-14xy-2y/x-2xy-y的值.
x+3xy-y=0
∴x-y=-3xy
2x-14xy-2y/x-2xy-y
=[(2x-2y)-14xy]/[(x-y)-2xy]
=[2(x-y)-14xy]/[(x-y)-2xy]
=(-6xy-14xy)/(-3xy-2xy)
=-20xy/(-5xy)
=4

x+3xy-y=0
x-y=-3xy

2x-14xy-2y/x-2xy-y
=[2(x-y)-14xy]/[(x-y)-2xy]
=(-6xy-14xy)/(-3xy-2xy)
=20/5
=4

x+3xy-y=0
x-y=-3xy
(2x-14xy-2y)/(x-2xy-y)=(2(x-y)-14xy)/(x-y-2xy)=(2*(-3xy)-14xy)/(-3xy-2xy)=(-20xy)/(-5xy)=4

x-y=-3xy
2x-14xy-2y/x-2xy-y=2-(10xy/x-2xy-y)=2-(10xy/-3xy-2xy)=2-(10xy/-5xy)=2+2=4


因为x+3xy-y=0
所以x-y=-3xy
所以
(2x-14xy-2y)/(x-2xy-y)
=(2x-2y-14xy)/(x-y-2xy)
=(-6xy-14xy)/(-3xy-2xy)
=(-20xy)/(-5xy)
=4