Consider the line $r$ passing through the two points $A(1, -2, 0)$ and $B(2, 3, -1)$, determine the Cartesian equation of the spherical surface with center $C(1, -6, 7)$ and tangent to $r$.
Consider the line $r$ passing through the two points $A(1, -2, 0)$ and $B(2, 3, -1)$, determine the Cartesian equation of the spherical surface with center $C(1, -6, 7)$ and tangent to $r$.