问题描述: 解方程组3(x+y)-4(x-y)=4,x+y除以2+x-y除以6=1 1个回答 分类:数学 2014-09-17 问题解答: 我来补答 x+y除以2+x-y除以6=1? 再问: 3(x+y)-4(x-y)=4,(x+y)/2+(x-y)/6=1 写对就采纳。要完整 再答: 3(x+y)-4(x-y)=4 得 -X+7y=4(1) (x+y)/2+(x-y)/6=1(2) (2)去分母:3(X+Y)+(X-Y)=6 得 4x+2y=6 得 2x+y=3 (3) (1)*2 :-2x+14y=8 (4) (4)+(3):y=11/15 将y代入x=17/15再问: 对不起,题目写错了.应该是3(x+y)-4(x-y)=-9,(x+y)/2+(x-y)/6=1 再答: 3(x+y)-4(x-y)=9 得 -X+7y=9(1) (x+y)/2+(x-y)/6=1(2) (2)去分母:3(X+Y)+(X-Y)=6 得 4x+2y=6 得 2x+y=3 (3) (1)*2 :-2x+14y=18 (4) (4)+(3):y=7/5 将y代入x=4/5 展开全文阅读