3/x+y+10/x-y=-5 2/x+y-15/x-y=1
问题描述：
3/x+y+10/x-y=-5 2/x+y-15/x-y=1
两个方程组,求x,y
答
若x+y,x-y为分母,则:
设3/(x+y)+10/(x-y)=-5为①,2/(x+y)-15/(x-y)=1为②
先①*3,②*2得
9/(x+y)+30/(x-y)=-15 ③,4/(x+y)-30/(x-y)=2 ④
③+④得x+y=-1即y=-x-1.
代入①式得x=2,y=-3
不知过程是否有错,请查收