In 3D Euclidian Vector geometry, if given the 4 vertices of a (Triangular) pyramid:

A (12,0,0) B(0,6,0) C(0,0,4) and O (origin: 0,0,0)

how can you find the sphere that passes through those vertices?

NB: this sphere is S: x² + y² + z² -12x -6y -4z = 0 but i want to know HOW you find this??

Help VERY appreciated thanks!