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A Regular Polygon with 97 sides: Area, Perimeter, Interior and Exterior Angles, Inradius, Circumradius



A regular polygon with 97 sides where the length of each side is 9 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 97 sides. What are the interior angles and exterior angles? 
If the length of each side is 9 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 97

Perimeter of a polygon with 97 sides = (side length) x 97 = 873 units

Area of a polygon with 97 sides = (n x Sidecot (Π/n))/4 = (n x 9cot (Π/97))/4 = 60627.09 square units

Sum of the interior angles of a polygon with 97 sides = 
 (n-2) x 180 degrees =  (97-2) x 180 degrees = 17100 degrees

Interior Angle of a polygon with 97 sides = (n-2) x 180/n degrees = (97-2) x 180/97 degrees = 176.28 degrees 

Exterior angle of a polygon with 97 sides = 180 - Interior Angle = 180 - 176.28 = 3.71 degrees

Inradius = Radius of In-circle = (side length) x cot (Π/97) = 9 x cot 1 = 277.78 units

Circumradius = Radius of Circum-circle = (side length) x cosec (Π/97) = 9 x cosec 1 degrees = 277.93 units

Symmetry Group = D97  97 rotational symmetries and 97 reflection symmetries. The "D" stands for di-hedral. 




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