x^2+y^2+z^2-2x+4y-6z+14=0 (x^2-2x+1)+(y^2+4y+4)+(z^2-6z+9)=0 (x-1)^2+(y+2)^2+(z-3)^2=0 x=1,y=-2,z=3 (x-y-z)^2010=0^2010=0