问题描述: 已知xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值 1个回答 分类:数学 2014-12-09 问题解答: 我来补答 (5x-xy+5y)/(3xy-x-y)=[5(x+y)-xy]/[3xy-(x+y)]=[5(x+y)-2(x+y)]/[6(x+y)-(x+y)]=1/2 展开全文阅读