若x^2+2x+y^2-6y+10=0,则x-y
问题描述:
若x^2+2x+y^2-6y+10=0,则x-y
答
x^2+2x+y^2-6y+10=0
(x+1)^2 + (y-3)^2 = 0
x = -1,y = 3
x-y = -1 -3 = -4