Octagon
Pronunciation: /ˈɒk.təˌgɒn/ Explain
Click on the blue points and drag them to change the figure.
| Manipulative 1 - Octagon Created with GeoGebra. |
Click on the blue points and drag them to change the figure.
| Manipulative 2 - Regular Octagon Created with GeoGebra. |
|
A octagon is any eight sided
polygon. A
regular octagon is an
eight-sided polygon with sides of equal length.
As long as the sides do not intersect,
the figure in manipulative 1 is an octagon.
Octagon Facts
Name | Value |
---|
Central Angle | ![beta=45 degrees or p/4 radians.](../../equations/o/octagoneqn01.png) |
Vertex Angle | ![alpha=135 degrees or (3pi)/4 radians.](../../equations/o/octagoneqn02.png) |
Exterior Angle | ![gamma=225 degrees or (5pi)/4 radians](../../equations/o/octagoneqn03.png) |
Inradius | ![r=(1/2)*(1+square root(2))](../../equations/o/octagoneqn04.png) |
Circumradius | ![(1/2)*square root(4+2*square root(2)](../../equations/o/octagoneqn05.png) |
Area | ![r=2*(1+square root(2))s^2](../../equations/o/octagoneqn06.png) |
Table 1 |
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Examples of Octagons
References
- McAdams, David E.. All Math Words Dictionary, octagon. 2nd Classroom edition 20150108-4799968. pg 129. Life is a Story Problem LLC. January 8, 2015. Buy the book
Cite this article as:
McAdams, David E. Octagon. 3/25/2019. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/o/octagon.html.
Image Credits
Revision History
12/21/2018: Reviewed and corrected IPA pronunication. (
McAdams, David E.)
9/5/2018: Removed broken links, updated license, implemented new Geogebra protocol, implemented new markup. (
McAdams, David E.)
12/21/2009: Added "References". (
McAdams, David E.)
12/30/2008: Changed equations to images. (
McAdams, David E.)
7/1/2008: Initial version. (
McAdams, David E.)