A twenty-one-ogon.
Icosikaihenagon, or also known as Henicosagon.
A polygon with 6 sides is a hexagon and a polygon with 8 sides is an octagon
No the sides of a polygon can not cross
There is no formula for how many sides there are in a polygon; the name of the polygon shows how many sides it has.
An icosikaihena is a polygon with 21 sides
A polygon with 21 sides is called an Icosagon.
icosikaihenagon
It will have 21 sides or a 21-gon
So, the Sum of the interior angles for a 21 – sided polygon is equal to 3420°.
A twenty-one-ogon.
Icosikaihenagon, or also known as Henicosagon.
21
By using the polygon diagonal formula or the quadratic equation formula in which in both formulae they work out that the polygon in question has 21 sides.
It will have: (3420+360)/180 = 21 sides
The term for a 21 sided polygon is an icosikaihenagon. Icosi is the Greek for the numerical 20 and henagon means 1.
Exterior angles for n sides = 360/n = 17.14, n = 360/17.14 = 21 sides