What is (3 + 2i) (4 + 4i)
5i is equal to -5.
Write the equation of a circle with a center at (-5, 4) and a radius of 4.
What is the radius of a circle with a center at (4, 2) and has (2, 4) on the circle.
The center and the radius of :(x-5)^2 + (y+7)^2 =9 is...