Centre lies at the midpoint of the diameter which is ½(4-2,2-2)=(1,0), so the equation of the circle will look like: (x-1)2+y2=r2, where r is the radius, and:
r2=(-2-1)2+(-2-0)2=32+22=13, (x-1)2+y2=13 is the equation of the circle.

A(-2,-2) and B(4,2) are the given points (AB is the diameter). O is the centre at (1,0).
C(1+√13,0) and D(1-√13,0) are the x-intercepts.
E(-2,2) and F(3,-3) are two more points in the circle.