已知Y-x=3xy,求(5x+3xy-5y)÷(x-2xy-y)

问题描述:

已知Y-x=3xy,求(5x+3xy-5y)÷(x-2xy-y)

将条件y-x=3xy代入式中可化简成4(x-y)/(x-y-2xy),再将x-y=-3xy代入化简式中得到结果12/5

将后面式子中有关于y-x的项以xy代换
原式=(-15xy+3xy)/(-3xy-2xy)=-12xy/-5xy=2.4

(5x+3xy-5y)÷(x-2xy-y)
=(-15xy+3xy)/(-3xy-2xy)
=-12/(-5)
=2.4