问题描述: xy=6,x-y=5,x^2y+xy^2 1个回答 分类:数学 2014-12-04 问题解答: 我来补答 (x+y)" = (x-y)"+4xy = 25 + 24 =49x+y = ±7x"y+xy" = xy(x+y) = ±42 展开全文阅读