Circle

A circle is a geometrical figure where all its points are equidistant from a single point (the center). This distance is called the radius.

A circle is empty, a filled circle is a disc.

Properties

Perimeter

The perimeter of a circle is given by $2\pi r$, where $r$ is the radius of the circle.

Area

The area or a circle is given by $\pi r^{2}$.

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