posted by Rin-chan-san .
Sketch the sets of complex numbers in the complex plane that satisfy the following:
I'm not sure, but are you supposed to rearrange the whole thing to |z|=a+bi? So, part b would be |z|=2+3i.
all are circles of radius 2, with center at various numbers.
|z-c| = r has center at c.
|z|^2 = x^2+y^2
That's why the curves are circles.