help!

josh123

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Oct 5, 2005
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52
Can someone show me how to do this and find the answer?

Find the center and radius of the circle given by
(x - 2)2 + (y + 3)2 = 0.25
 

stapel

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When a circle equation is in the form:

. . . . .(x - h)<sup>2</sup> + (y - k)<sup>2</sup> = r<sup>2</sup>

...as yours is, just read off the center (h, k) and radius r directly from the equation.

Eliz.
 

josh123

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Oct 5, 2005
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52
so would this be the answer? Center at (-2, 3) and radius equal to 0.5
 

stapel

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The radius is correct, but check your signs on h and k. For instance, if h = -2, then x - h = x - (-2) = x + 2, but "x + 2" isn't what is in your equation.

Eliz.
 

josh123

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is this right? Center at (2, -3) and radius equal to 0.5
 

josh123

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52
Am I right?
 

stapel

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Yes.

Eliz.
 
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