Decagon (EntityTopic, 12)

(Difference between revisions)

Latest revision as of 16:20, 26 March 2017

A decagon is a polygon with 10 sides. It is the truncated pentagon.

The coordinates of a regular decagon are:

(0, ±2φ)
(±1, ±√(3+4φ)
(±(1+φ), ±√(2+φ)

⁵∕₂ · √((5+2√5)/2) · l²

(

Dual: Self-dual

Notable Dishapes
Flat:	triangle • square • pentagon • hexagon • octagon • decagon
Curved:	circle

@@ Line 1: / Line 1: @@
-<[#ontology [kind topic] [cats 2D Regular Flat Shape]]>
+<[#ontology [kind topic] [cats 2D Regular Polytope] [alt [[freebase:01wb3b]] [[wikipedia:Decagon]]]]>
 {{STS Shape
 | dim=2
-| elements=10, 10
+| elements=10 [[digon]]s, 10 [[point]]s
 | genus=0
 | ssc=G10
@@ Line 8: / Line 8: @@
 | extra={{STS Matrix|
 0
-1}}{{STS Uniform polytope
+1}}{{STS Polytope
-| schlaefli={10}
+| dual=''self-dual''
-| vfigure=[[Digon]], length 1
+| bowers=Dec}}{{STS Uniform polytope
-| dual=''Self-dual''
+| schlaefli={10}, t{5}
+| dynkin=x10o, x5x
+| vfigure=[[Digon]], length √((5+√5)/2)
 }}}}
+A decagon is a polygon with 10 sides. It is the truncated pentagon.
+==Coordinates==
+The coordinates of a regular decagon are:
+<blockquote>(0, ±2φ)<br>(±1, ±√(3+4φ)<br>(±(1+φ), ±√(2+φ)</blockquote>
+==Equations==
+*The area of a regular decagon is:
+{{Over|5|2}} &middot; √((5+2√5)/2) &middot; ''l''<sup>2</sup>
+(<[#polytope [id -10]]>
 {{Dishapes}}