# Circle

A circle is the set of points that are a fixed distance r, called the radius, from a fixed point (x, y), called the center. It can be thought of as a special case of an ellipse when ${\displaystyle a^{2}=b^{2}}$
The equation for the circle of radius r centered at (0, 0) is ${\displaystyle x^{2}+y^{2}=r^{2}}$
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