Distance from point in circle to edge of circle The situation is as follows:
I have a circle with a diameter of $20$ and a center at $(0,0)$.
A point $P$ inside that circle is at $(2,0)$.
How do I calculate the distance from $P$ to the edge of the circle for a given angle $\theta$?

The distance from $(2,0)$ to $(20,0)$ + the distance from $(2,0)$ to $(0,0)$ equals the radius.
