
Patrick B. answered 08/25/20
Math and computer tutor/teacher
We need 4 equations, as Pc=(Xc, Yc, Zc) is the center, and radius are all unknown:
You can find the distance between P and C
and
the distance between Q and C
where C=(Xc,Yc,Zc) where C is the center.
since they are on the circle:
(x1 - xc)^2 + (y1-yc)^2 + (z1-zC)^2 = R^2
and
(x2-xC)^2 + (y2-yC)^2 + (z2-Zc)^2 = R^2