( n x 180 ) - 360wheren is the number of sides.In other words,take the number of sides or your polygon and multiply that by 180.then, subtract 360 from that result.that is your answer.An octadecagon has 18 sides.( 18 x 180 ) - 360 = 2880The sum of the interior angles of an octadecagon is 2880 degrees.
Hendecagon has 11 sides,dodecagon has 12 sides,triskaidecagon has 13 sides,tetradecagon has 14 sides,pentadecagon has 15 sides,hexadecagon has 16 sides,17 sides is heptadecagon,octadecagon have 18 sides,enneadecagon has 19 sides,20 sides is called as icosagon. The prefix of that 9 polygons is Greek. A polygone with 4 sides is called a quadrilateral.
11 Undecagon, Hendecagon 12 Dodecagon 13 Tridecagon, Triskaidecagon 14 Tetradecagon, Tetrakaidecagon 15 Pentadecagon, Pentakaidecagon 16 Hexadecagon, Hexakaidecagon 17 Heptadecagon, Heptakaidecagon 18 Octadecagon, Octakaidecagon 19 Enneadecagon, Enneakaidecagon 20 Icosagon
360
The name of a 18 sided figure is an octadecagon or octakaidecagon. As you can see the prefix octa- means 8, and deca- means 10. It has 18 sides and 18 vertices,
Octadecagon
octadecagon or octakaidecagon
An Octadecagon
An octadecagon
An octadecagon is an 18 sided polygon.
( n x 180 ) - 360wheren is the number of sides.In other words,take the number of sides or your polygon and multiply that by 180.then, subtract 360 from that result.that is your answer.An octadecagon has 18 sides.( 18 x 180 ) - 360 = 2880The sum of the interior angles of an octadecagon is 2880 degrees.
An eighteen-sided shape is called an octakaidecagon, or octadecagon.
It has 18
Provided we are talking about a 2D figure with straight sides, it is an octadecagon.
Hexadecagon (16 sides) and Octadecagon (18 sides) both fit. Am I missing something?
An octadecagon - 18 sides
It has 18 sides (an octadecagon) because the number of identical angles on the polygon must always equal 360 degrees.