Answer:
( 2, - 1 )
Step-by-step explanation:
( x - h )² + ( y - k )² = r²
( h, k ) are coordinates of the center of a circle with radius r
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x² + y² - 4x + 2y - 11 = 0
( x² - 4x + 4 ) - 4 + ( y² + 2y + 1 ) - 1 - 11 = 0
( x - 2 )² + ( y + 1 )² = 4²
Coordinates of the center of a circle are ( 2, - 1 )