Talking about a "2-D polygon" is the same as talking about a "polygon." By definition a polygon is a 2-dimensional figure, so all polygons are 2-dimensional and anything that is not 2-dimensional cannot be a polygon.
Of course, not all 2-dimensional figures are polygons.
rectangeler polygon
An octagon is a two-dimensional polygon with eight sides which can be regular or irregular
As a 2D polygon shape it is an 8 sided octagon.
Yes a triangle is a 2D polygon shape
A polygon with seven sides is a heptagon.
hexagon
A hexagon is a 6-sided polygon 2D shape.
It is because a polygon is 2D figure while a cube is a 3D figure.
An hexagon is a 2 dimensional polygon that has 6 sides
A ten-sided 2D polygon is known as a decagon.
Irregular polygon
A circle.