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Number of diagonals = 18*(18-3)/2 = 135
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∙ 12y ago
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How many diagonals does an octadecagon have?
The formula for the number of diagonals (that is, lines joining non-adjacent vertices) belonging to any shape is n(n-3)/2. Therefore, an eighteen-sided polygon has 18 x (18 - 3)/2 = 135 diagonals.
What is the name off an 18 sided shape?
All I can tell you is that a 16 sided shape is called a Hexadecagon
What do you call a 18 sided shape?
Dooctahedron
A 18 sided 2D shape?
Tetrahaidecahedron
What is a 18 sided 3D shape called?
Octadecadron
How many diagonals can be drawn from any vertex of a 20-sided polygon?
It is 18 diagonals
How many diagonals does an octadecagon have?
The formula for the number of diagonals (that is, lines joining non-adjacent vertices) belonging to any shape is n(n-3)/2. Therefore, an eighteen-sided polygon has 18 x (18 - 3)/2 = 135 diagonals.
How many sides does a 18 sided regular polygon have?
If you say this shape is 18 sided i would guess it has 18 sides. ;)
What is the special features of the dodecahedron?
It is a 3-dimensional simply connected shape with 12 polygonal faces. That is it! It can have as few as 8 or as many as 20 faces, as few as 18 or as many as 30 edges, the faces can all be triangles or the shape can have an endecagonal (11-sided) face. It can have between 9 and 170 diagonals.
What is the name off an 18 sided shape?
All I can tell you is that a 16 sided shape is called a Hexadecagon
What do you call a 18 sided shape?
Dooctahedron
What is the name of an 18 sided 3d shape?
no
A 18 sided 2D shape?
Tetrahaidecahedron
What is the name of an 18 sided shape?
octadecagon
What is an 18 sided shape?
enneadecagon or enneakaidecagon
18 sided 3d shape?
An 18 sided shape is called a octadecagon. This refers to both 2 dimensional and 3 dimensional shapes in a mathematical sense.
What is a 18 sided 3D shape called?
Octadecadron
