<|system|>
Find the center of the circle with equation $x^2 - 6x + y^2 + 2y = 9$.</s>.
<|user|>
Can you answer based on context?
<|assistant|>
Completing the square, we get $(x - 3)^2 + (y + 1)^2 = 19$. Therefore, the center of the circle is $(3, -1)$.