There are a number of polygons that are similar to it but if you mean things that look like decagons than nonagon, undecagon, dodecagon, and octagon.
An undecagon has 11 sides.
11 sides
Hendecagon or undecagon
It is not clear what exactly you want to add.
a shape with eleven sides is called a undecagon
hexagon, heptagon, octagon, nonagon, decagon, undecagon, dodecagon .... etc
There are a number of polygons that are similar to it but if you mean things that look like decagons than nonagon, undecagon, dodecagon, and octagon.
An undecagon has 11 sides.
An undecagon is an 11 sided polygon
undecagon has 43 diagonals (answer by erwin handsome)
An undecagon, or figure with 11 sides. has an interior angle of 147o
a undecagon has eleven sides and angles.
There are 11 triangles in an undecagon. The number of sides of a polygon is the number of triangles it has.
An undecagon is an 11 sided shape and its interior angles add up to 1620 degrees
An undecagon
Hendecagon or undecagon