a) The equation of the circle centered at $1+2i$ with radius $1$ can be written as $[ z\overline{z} + pz + q \overline{z} + r = 0.]$What is the ordered triple $(p, q, r)$?
b) Let $A_1 A_2 \dotsb A_{11}$ be a regular 11-gon inscribed in a circle of radius 2. Let $P$ be a point, such that the distance from $P$ to the center of the circle is 3. Solve $PA_1^2 + PA_2^2 + \dots + PA_{11}^2.$
I have no clue how to get started on these problems.