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### Polygons and Circles

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Date: 4/3/96 at 14:38:10
From: "Rebecca J. White"
Subject: math question

Dear Dr. MATH,

Is a circle a polygon?  Why or why not?

What is a 3-D shape that has 18 sides called?

From Ryan, Amanda, and Danielle
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Date: 4/3/96 at 16:56:49
From: Doctor Jodi
Subject: Re: math question

Hi Ryan, Amanda, and Danielle!  Thanks for your questions.

Since the Greek prefix for 18 is octakaideca (which means eight
and ten), we could call a polyhedron with 18 sides an
octakaidecahedron.  Boy is that a name for a shape!  Can you think
of any ways to make one of those?

What might you nickname an octakaidecahedron?

As for calling a circle a polygon.. Boy this is a very interesting
question!  Well, as you add more and more sides to a polygon, it
does start to look more and more like a circle.  So some people,
even some mathematicians, have called a circle an "infinite
polygon"--that is, a polygon with infinitely many sides.  Other
people heartily disagree.

I'm not sure what to think about the whole thing... What about you
three?

-Doctor Jodi,  The Math Forum

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Associated Topics:
Middle School Conic Sections/Circles
Middle School Geometry
Middle School Triangles and Other Polygons

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