it is called the sum just like in adding.
The sum of all the sides of a given shape is the perimeter of that shape.
The shape is called a decagon. If all the sides and angles are the same, it is called a regular decagon.
This shape is called an icosikaitera. All of the sides of the icosikaitera are all of the same equal length.
It is an irregular shape or polygon that doesn't have all sides equal
A six sided shape is called a hexagon.If all the sides have the same length and all the internal angles are the same it is a Regular hexagon.
Regular polygons
A shape with eight sides is always an octagon. If all angles and sides are equal, it is called a regular octagon.
A shape that has five sides is called a pentagon. A normal pentagon has all five sides that are the same length.
Six sided shapes are called hexagons. If all 6 sides are the same size, then the shape is called a regular hexagon.
irregular quadrilateral
A shape with nine corners is called a nonagon. In geometry, a nonagon is a polygon that has nine sides and nine angles. It can be regular, where all sides and angles are equal, or irregular, where the sides and angles are not necessarily equal.
Ah, a shape with 5 sides is called a pentagon. Isn't that a lovely name? Just imagine all the beautiful things you can create with a pentagon in your artwork. Keep exploring and embracing different shapes, my friend.