Answer:
The center is ( 1,-3) and the radius is 3
Explanation:
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-1)^2 + (y+3)^2= 9
(x-1)^2 + (- -3)^2= 3^2
The center is ( 1,-3) and the radius is 3