A function f is defined on the complex numbers by f(z) = (a+bi)z, where a and b are positive real numbers. Each point in the image of f is equidistant from the point z and the origin. Given that |a+bi| = 8, find a and b.
Enter your answer as an ordered pair: (a,b)
I tried this question 3 times but I'm a little stuck on where to go after a couple steps.. can someone help please??