How to find the center and the radius of the circle

x^2+2x+y^2-8y=4


im really lost ive looked at examples but i cant figure it out someone please help :(

x^2 + 2x + y^2 - 8y = 4
(x^2 + 2x) + (y^2 - 8y) = 4
*use completing the squares for both x & y equations inside the parentheses
(x^2 + 2x + 1) - 1 + (y^2 - 8y + 16) - 16 = 4
(x+1)^2 + (y-4)^2 = 4 + 16 + 1
(x+1)^2 + (y-4)^2 = 21

therefore, the center is at (-1,4) and the radius is equal to the square root of 21.