已知x-y=-3xy,则代数式x-2xy-y/2x-14xy-2y的值为?

问题描述:

已知x-y=-3xy,则代数式x-2xy-y/2x-14xy-2y的值为?

此题主要是把x-y用-3xy代替就可作了
x-2xy-y/2x-14xy-2y
=(-3xy-2xy)/2(x-y)-14xy
=-5xy/(-6xy-14xy)
=-5xy/-20xy
=1/4