Got to be a geek and respond to freak107. I'm afraid that a circle is not a polygon with an infinite number of corners. It can be approximated (i.e. get close to the true solution) by a polygon as the number of corners tends to infinity but it will never be a true circle. You could however say a circle is a polygon with one side and no corners but there are some geometrists out there who would disagree with that too as technically "polygon" means "many sided".
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