# Circumscribed circle - inscribed circle area formula

#### guss

I'm looking for a formula that subtracts the area of an inscribed circle of a shape from the circumscribed area of the shape. I've confused myself on this one and can't seem to figure it out.

The shape is a regular polygon (all sides and angles are equal). What should be given to "plug in" is each side is of length L and there are s sides.

Can anyone help me? Thanks!

#### guss

Got it!

$$\frac{L^{2} \pi\ }{4}$$

Where $$L$$ is the length of each side. Works for any regular polygon.

Sorry, you can close this thread if you please.

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