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Graph a Circle

You know circles are round. This is pretty simple. But, the mathematical description of circles can get quite confusing, since there is a set equation for a circle, including symbols for the radius, and center of the circle.

This page will show you how these items reflect the final look of a circle on a plot.

To the right are all possible combinations of equations for a circle. Fill in the one that looks most like the one you ’ re working on, then click "Draw It!"

Fill in only one of these four circle forms: 
x2 + y2 = 


(x)2 + y2 = 


x2 + (y )2 = 


(x)2 + (y )2 =

Set the axes ranges of your plot:
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Help typing in your math problems