Question

(x-2)^2+(y-3)^2+(z+7)^2=144

Answer 1

х²-4х+4+у²-6у+9+z²+14z+49=144
x²-4x+y²-6y+z²+14z+62=144
x(x-4)+y(y-6)+z(z+14)=144-62
x(x-4)+y(y-6)+z(z+14)=82