Find the center and radius

x^2  + y^2  + 4x  + 2y  - 4   = 0

x^2 + 4x + 4  + y^2 + 2y  + 1  =  4 + 4 + 1

(x + 2)^2  +  (y + 1)^2   =  9

The center is  ( -2, -1)  and the radius is 3

EDIT TO CORRECT ASLIGHT ERROR  !!!

r²=9

The radius is 3.