Not all polygons have an 'official' name. It is quite acceptable to call a polygon using the number of sides it has. For example a 101ogon.
There is a list of some polygons names listed in the related question.
Chat with our AI personalities
There are not many common nonagonal shapes. Some coins are nonagonal.
One shape cannot be congruent: you need two (or more) shapes which can be congruent to each other.
Some of them are: triangle, quadrilateral, pentagon, hexagon, heptagon, octagon, nonagon, decagon ..... etc
A nonagon here are all the shapes and sides for help all are 2D shapes Circle=1 Not sure about this one Triangle=3 Square=4 Pentagon=5 hexagon=6 heptagon=7 octagon=8 nonagon=9 decagon=10
Heptagon, octagon, nonagon, decagon, hendecagon, and dodecagon. There are many more.