Decagon
Pronunciation: /ˈdɛk.əˌgɒn/ Explain
Click on the blue points and drag them to change the figure.
 Manipulative 1  Regular Decagon Created with GeoGebra. 

A decagon is a ten sided
polygon.^{[1]}
A regular decagon is a ten sided
regular polygon.
In table 1, a is the length of a side and n is the number of
sides.
Formula for regular decagon
Formula  Description 
 Number of sides 
 Central angle 
 Area 
 Interior angle 
 Exterior angle 
 Inradius 
 Circumradius 
Table 1 

Geometric Nets
A geometric net
is a
2dimensional
shape that folds into a
3dimensional
polyhedron. Some geometric nets that contain at least 1 decagon are shown in table 2.
References
 McAdams, David E.. All Math Words Dictionary, decagon. 2nd Classroom edition 201501084799968. pg 54. Life is a Story Problem LLC. January 8, 2015. Buy the book
 Venugopal, Valsaraj. Higher Elementary Geometry. www.archive.org. 1st edition. pg 5. Last Accessed 7/3/2018. http://www.archive.org/stream/higherelementary033043mbp#page/n20/mode/1up/search/decagon. Buy the book
 Hornbrook, A. R.. Concrete geometry for beginners. pg 127. www.archive.org. American Book Company. 1895. Last Accessed 7/3/2018. http://www.archive.org/stream/concretegeometry00hornrich#page/127/mode/1up/search/decagon. Buy the book
More Information
 McAdams, David E.. Geometric Nets. lifeisastoryproblem.com. Life is a Story Problem LLC. 3/12/2009. http://www.lifeisastoryproblem.com/explore/index_net.html.
Cite this article as:
McAdams, David E. Decagon. 12/21/2018. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/d/decagon.html.
Image Credits
Revision History
12/21/2018: Reviewed and corrected IPA pronunication. (
McAdams, David E.)
7/3/2018: Removed broken links, updated license, implemented new markup, implemented new Geogebra protocol. (
McAdams, David E.)
1/22/2010: Added "References". (
McAdams, David E.)
1/21/2009: Added geometric nets containing decagons, Geometric Nets. (
McAdams, David E.)
12/4/2008: Initial version. (
McAdams, David E.)