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Which are the center and radius of the circle with this equation? x^(2)-4x+y^(2)+2y=0

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Final Answer:

The center of the circle with the equation x^2 - 4x + y^2 + 2y = 0 is (2, -1), and the radius is 5.

Step-by-step explanation:

To find the center and radius of the circle, complete the square for both the x and y terms. Start with the given equation:

x^2 - 4x + y^2 + 2y = 0

For the x-terms:

x^2 - 4x + 4 = (x - 2)^2

For the y-terms:

y^2 + 2y + 1 = (y + 1)^2

Now, rewrite the equation:

(x - 2)^2 + (y + 1)^2 = 5^2

This is the standard form of the equation for a circle (x - h)^2 + (y - k)^2 = r^2, where (h, k) is the center and r is the radius. Thus, the center is (2, -1), and the radius is 5.

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