You can put this solution on YOUR website!
If you know the radius (distance from the center to a vertex), then area will be:
where is the number of sides and is the radius
if
then
You can put this solution on YOUR website! 100-gon with a radius of 5
what is the area
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As the number of sides increases, the area approaches that of a circle.
100 is a lot of sides.
Area =~ 78.54 sq units