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Math Help - Center and radius of a circle?

  1. #1
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    Center and radius of a circle?

    How do I find the radius and center of the circle x^2 + 4x + y^2 = 5?
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  2. #2
    Eater of Worlds
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    Complete the square.

    x^{2}+4x+4=(x+2)^{2}

    (x+2)^{2}+(y-0)^{2}=9

    The circle is centered at (-2,0) and has radius 3. See?.
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