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### Pentagram

```
Date: 12/08/2001 at 13:09:15
From: Stephanie Shipwash
Subject: Polygons

Is a 5-pointed star (on a flag), a decagon, or just 5 triangles?

Thanks,
Stephanie
```

```
Date: 12/08/2001 at 13:18:20
From: Doctor Sarah
Subject: Re: Polygons

Hi Stephanie - thanks for writing to Dr. Math.

See George Hart's Web page on Pentagrams:

http://www.georgehart.com/virtual-polyhedra/pentagram.html

"Pentagrams are "five-pointed stars." They are regular polygons with
five vertices and five edges; that's all. The sides just happen to
cross each other at five points of intersection which outline the
small interior pentagon, but those are not vertices and the smaller
segments are not complete sides. Mathematically, the pentagram is
special for being the simplest nonconvex regular polygon."

- Doctor Sarah, The Math Forum
http://mathforum.org/dr.math/
```
Associated Topics:
Elementary Definitions
Elementary Geometry
Elementary Triangles and Other Polygons
Middle School Definitions
Middle School Geometry
Middle School Triangles and Other Polygons

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