I suggest you forget about memorizing fancy names - which really serve no useful purpose - and just call them "20-sided polygon", "21-sided polygon", etc.
Duodecagon <--wrong... a duodecagon is a 12-sided polygon. icosagon is a 20 sided polygon.
A 20-sided polygon is an icosagon.(see related link)
The name of a 20 sided polygon is Icosagon.
A 20-sided polygon is called an icosagon.
A 20-sided polyhedron is an icosahedron. A 20-sided polygon is an icosagon.
It is an icosagon.
An icosagon.
I suggest you forget about memorizing fancy names - which really serve no useful purpose - and just call them "20-sided polygon", "21-sided polygon", etc.
Duodecagon <--wrong... a duodecagon is a 12-sided polygon. icosagon is a 20 sided polygon.
A 20-sided polygon is an icosagon.(see related link)
The name of a 20 sided polygon is Icosagon.
A 20-sided polygon is called an icosagon.
The name of a 20 sided polygon is Icosagon.
icosihenagon= 21-sided polygon icosihenagon= 21-sided polygon
Icosikaihexagon Icosikai is 20 and hexagon is 6
The name of a sided polygon is Octaconpentagon.