`x^2 + y^2 + z^2 + 12x - 2y+ 4z+ 16= 0`

`x^2 + y^2 + z^2 + 12x-2y+ 4z-16= 0`

`x^2 + y^2 + z^2 -12x+ 2y- 4z+ 16= 0`

`x^2 + y^2 + z^2 -12x+ 2y- 4z+ 25= 0`