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Topic: Names of polygons
Replies: 26   Last Post: Apr 29, 2008 12:08 PM

 Messages: [ Previous | Next ]
 Gary Martin Posts: 22 Registered: 12/6/04
Re: 11-gon
Posted: Oct 24, 1994 6:18 AM

>Since the 13-gon, 14-gon, 18-gon, 19-gon are not constructable with
>compass and straight edge, other than for linguistic curiosity, why would
>one want to name them?

(a) I can easily construct a 13-gon. Draw a circle. Pick 13 points on the
circle. Connect adjacent points. A 13-gon. (Note: the circle is only for
convenience; not strictly necessary.) However, a regular 13-gon is not
constructible.

(b) Do non-constructible polygons exist (in the mathematical sense)? I
would emphatically argue that they do, and that they *are* of interest at
least of as much interest as the 24-gon.

I feel compass-straight edge constructibility is far over-rated in
geometry. It is of a rather abstract nature; certainly one can define a
regular 13-gon and even do a pretty good of drawing one, given a protractor
or a computer. So what if you can't do a classical construction? Is this of
any great importance?

Nonetheless, a very informative discussion of names; never heard some of
these before! My students have come up with interesting suggestions (i.e,
unidecagon) but I never really knew the generally accepted terms!

g.

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Date Subject Author
10/22/94 SON TO
10/22/94 BeckyP
10/23/94 CLEMENTS@ubvms.cc.buffalo.edu
10/23/94 Michael Keyton
10/26/94 David Masunaga
10/27/94 Michael Keyton
9/2/03 Richard Laferty
10/24/94 Gary Martin
10/24/94 John Conway
11/29/00 Jeffrey C. Jacobs
10/24/94 John Conway
10/24/94 John Conway
10/24/94 John Conway
10/25/94 Michael Keyton
12/6/94 Keith Grove
12/17/98 Kim McCool
1/25/05 Mimi
12/7/94 John Conway
3/12/03 Bob Janet
10/13/03 Candice
10/14/03 John Conway
1/25/05 Chris or Terry Guay
4/29/08 Bob L Petersen
1/25/05 Mimi
3/31/08 Deja Warner