its called a septagon
It it a Heptagon
A 2-D shape with seven sides is called a HEPTAGON.
It is a Heptagon.
It is a 7 sided heptagon
A triangle as no other 2d shape can have 3 sides.
A 2D shape with 9 sides is called a Nonagon.
The shape of 2D is a flat surface.
A 2D shape that has four sides and is thirteen letters long is a quadrilateral.