What is 20 polygon?

A 20-sided polygon is called an icosagon. Here's some information about it:

• Definition: An icosagon is a polygon with 20 sides and 20 angles.

• Regular Icosagon: A regular icosagon has all sides of equal length and all angles equal in measure. Each interior angle of a regular icosagon measures 162 degrees.

• Interior Angles: The sum of the interior angles of any icosagon (regular or irregular) is 3240 degrees. This is calculated using the formula (n-2) * 180, where n is the number of sides.

• Exterior Angles: The sum of the exterior angles of any icosagon is always 360 degrees.

• Area: The area of a regular icosagon with side length a is given by the formula: Area = 5*a² * cot(π/20) ≈ 31.5687 * a²

• Symmetry: A regular icosagon has 20 lines of symmetry (10 through opposite vertices and 10 through the midpoints of opposite sides) and rotational symmetry of order 20.

• Construction: A regular icosagon is constructible using a compass and straightedge, as 20 is the product of a power of 2 and distinct Fermat primes (20 = 2² * 5).