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### A Regular Nonagon

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Date: 11/2/95 at 21:51:39
From: Anonymous
Subject: Is there a regular nonagon

I want to know if there is such a thing as a regular nonagon and
if not, why can't you get one?

I've tried by using "triangle paper" and using lots of different
angle measures and side lengths (trial and error) and haven't
gotten a regular nonagon yet. I'd like to know if I just haven't
tried hard enough and there is one, or if it is non-existing.

Please e-mail me at tjh@garden.net
Thanks- Tucker Hottes
```

```
Date: 11/5/95 at 16:29:21
From: Doctor Jeremy
Subject: Re: Is there a regular nonagon

There is such a thing.  As a matter of fact, for any whole number
that is three or greater, you can find a regular polygon with that
many sides.

The problem you had with getting a regular nonagon is that the
regular nonagon has a weird angle between the sides.  The angle
between each of the segments of the regular nonagon is 140 degrees
(measured from the inside).  Triangle paper is designed to work
with lots of angles like 30, 60, 90 degrees and so on.  140 isn't
one of them.  I'm not sure how you would draw one, at least using
such tools.  You probably could get one on a computer.

But yes, it does exist.  It's just very hard to draw.

-Doctor Jeremy,  The Geometry Forum

```
Associated Topics:
High School Geometry
High School Triangles and Other Polygons

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