What are the coordinates of the center of a circle with the equation x^2-6x+y^2+4y=20?

All help is appreciated.

The centre of the circle

C : (x-x1)² + (y-y1)² = r²
is at (x1,y1).
For the given circle, the centre can be found by completing the squares, namely:
x^2-6x+y^2+4y=20
(x-3)²-9 + (y+2)²-4 = 20
(x-3)² + (y+2)² =33
Can you find the centre of the circle?