They are called hendecagons.
a shape with eleven sides is called a undecagon
They are called endecagons or hendecagons.
They are called sides or edges.
Shapes with straight sides are called polygons
It is an undecagon which has 11 sides. Eleven sided shapes are usually called hendecagons, which uses the greek for eleven - Hendeka and corner -gon. However they can also be termed as undecagons or unidecagons.
An eleven sided shape is called a hendecagon.
They are called heptagons.
It is called Enneagon for eleven sides.
A shape w/ 11 sides is called a hendecagon.
Hexagon.
Nonagons.
a triangle