已知(x-y+3)2+2-y=0,则x+y=_.
问题描述:
已知(x-y+3)2+
=0,则x+y=______.
2-y
答
∵(x-y+3)2+
=0,
2-y
∴
,
x-y+3=0 2-y=0
解得
,
x=-1 y=2
则x+y=-1+2=1,
故答案为1.