Answer:
The center is (0,0) and the radius is 4
Explanation:
x^2+y^2=16.
The equation of a circle can be written in the form
(x-h)^2+(y-k)^2=r^2 where ( h,k) is the center and r is the radius
(x-0)^2+(y-0)^2=4^2
The center is (0,0) and the radius is 4