问题 填空题
若x,y为实数,满足
x-1
+(3x+y-1)2=0,则±
5x+y2
=______.
答案

x-1
+(3x+y-1)2=0

x-1=0
3x+y-1=0

解得

x=1
y=-2

则±

5x+y2
5×1+(-2)2 
=±3.

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