Suppose we have a square with vertices at$0, -6+13i, -19+7i, and -13-6i. Suppose that we want to multiply these points by a single complex number a+bi to get a square with vertices 0, 8+2i, 6+10i, and -2+8i. What is (a,b)?

so, you want (-6+3i)(a+bi) = 8+2i

a = -14/`4
b = -12/15
I'd check to make sure that works for the other vertices as well ...