What is the center and radius of the circle x^2 + y^2 - 6x + 10y + 9 = 0.

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The equation x^2 + y^2 - 6x + 10y + 9 = 0 has to be expressed in the form (x-a)^2 + (y-b)^2 = r^2

x^2 + y^2 - 6x + 10y + 9 = 0

=> x^2 - 6x + 9 + y^2 + 10y + 25 = -9...

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The equation x^2 + y^2 - 6x + 10y + 9 = 0 has to be expressed in the form (x-a)^2 + (y-b)^2 = r^2

x^2 + y^2 - 6x + 10y + 9 = 0

=> x^2 - 6x + 9 + y^2 + 10y + 25 = -9 + 9 + 25

=> (x - 3)^2 + (y + 5)^2 = 5^2

The center of the circle represented by x^2 + y^2 - 6x + 10y + 9 = 0 is (3, -5) and the radius is 5.

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