# Hard SAT Math Question 51 — Video Explanation | 1600.now

Source: https://1600.now/hard/51

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51

$x^2 - 18x + y^2 + 6y = -65$  
The equation above defines a circle in the $xy$-plane. What are the coordinates of the circle's center?

A

$(9,-3)$

B

$(-18,6)$

C

$(-9,3)$

D

$(18,-6)$