Sphere Tangent to a Plane
For sphere with centre $$C(a,b,c)$$ and radius $$r$$, tangency to plane:
$$Ax+By+Cz+D=0$$
requires:
$$\frac{|Aa+Bb+Cc+D|}{\sqrt{A^2+B^2+C^2}}=r$$
Usage
- Used to determine unknown sphere parameters under a plane-tangency condition.