Question

If (x+3)^2+(y-3)^2=0,then x+y=?

Answer 1

$(x + 3) {}^{2} + (y - 3) {}^{2} = 0 \\ x {}^{2} + 9 + 6x + y {}^{2} + 9 - 6y = 0 \\ x {}^{2} + y {}^{2} + 6x - 6y + 18 = 0$