已知y-x=3xy,则代数式2x-14xy-2y/x-2xy-y的值为
问题描述:
已知y-x=3xy,则代数式2x-14xy-2y/x-2xy-y的值为
答
∵y-x=3xy
∴x-y=-3xy
∴(2x-14xy-2y)/(x-2xy-y)
=[2(x-y)-14xy]/[(x-y)-2xy]
=(-6xy-14xy)/(-3xy-2xy)
=(-20xy)/(-5xy)
=4