Student Question

A circle has the equation x^2+y^2+2x-2y-14=0, determine the center and radius.

Expert Answers

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The equation of the circle is x^2+y^2+2x-2y-14=0. Write this in the standard form of a circle with center (h, k) and radius r: (x - h)^2 + (y - k)^2 = r^2

x^2+y^2+2x-2y-14=0

=> x^2 + 2x + 1 + y^2 - 2y + 1 = 16

=> (x + 1)^2 + (y - 1)^2 = 4^2

The center of the circle is (-1, 1) and the radius is 4.

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