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A regular nonagon where the length of each side is 2 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 2 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 18 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 2cot (Π/9))/4 = 24.72 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 2 x cot 20 = 5.49 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 2 x cosec 20 degrees = 5.84 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 3 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 3 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 27 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 3cot (Π/9))/4 = 55.63 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 3 x cot 20 = 8.24 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 3 x cosec 20 degrees = 8.77 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 4 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 4 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 36 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 4cot (Π/9))/4 = 98.9 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 4 x cot 20 = 10.98 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 4 x cosec 20 degrees = 11.69 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 5 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 5 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 45 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 5cot (Π/9))/4 = 154.54 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 5 x cot 20 = 13.73 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 5 x cosec 20 degrees = 14.61 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 6 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 6 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 54 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 6cot (Π/9))/4 = 222.54 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 6 x cot 20 = 16.48 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 6 x cosec 20 degrees = 17.54 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 7 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 7 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 63 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 7cot (Π/9))/4 = 302.9 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 7 x cot 20 = 19.23 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 7 x cosec 20 degrees = 20.46 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 8 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 8 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 72 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 8cot (Π/9))/4 = 395.63 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 8 x cot 20 = 21.97 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 8 x cosec 20 degrees = 23.39 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon 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 9 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 = 9

Perimeter of a nonagon = side x 9 = 81 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 9cot (Π/9))/4 = 500.72 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 9 x cot 20 = 24.72 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 9 x cosec 20 degrees = 26.31 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 10 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 10 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 90 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 10cot (Π/9))/4 = 618.18 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 10 x cot 20 = 27.47 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 10 x cosec 20 degrees = 29.23 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 11 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 11 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 99 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 11cot (Π/9))/4 = 748 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 11 x cot 20 = 30.22 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 11 x cosec 20 degrees = 32.16 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 12 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 12 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 108 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 12cot (Π/9))/4 = 890.18 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 12 x cot 20 = 32.96 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 12 x cosec 20 degrees = 35.08 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 13 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 13 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 117 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 13cot (Π/9))/4 = 1044.72 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 13 x cot 20 = 35.71 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 13 x cosec 20 degrees = 38 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 14 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 14 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 126 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 14cot (Π/9))/4 = 1211.63 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 14 x cot 20 = 38.46 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 14 x cosec 20 degrees = 40.93 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 15 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 15 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 135 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 15cot (Π/9))/4 = 1390.91 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 15 x cot 20 = 41.21 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 15 x cosec 20 degrees = 43.85 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 16 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 16 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 144 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 16cot (Π/9))/4 = 1582.54 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 16 x cot 20 = 43.95 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 16 x cosec 20 degrees = 46.78 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 17 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 17 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 153 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 17cot (Π/9))/4 = 1786.54 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 17 x cot 20 = 46.7 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 17 x cosec 20 degrees = 49.7 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 18 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 18 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 162 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 18cot (Π/9))/4 = 2002.91 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 18 x cot 20 = 49.45 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 18 x cosec 20 degrees = 52.62 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 19 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 19 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 171 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 19cot (Π/9))/4 = 2231.63 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 19 x cot 20 = 52.2 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 19 x cosec 20 degrees = 55.55 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 20 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 20 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 180 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 20cot (Π/9))/4 = 2472.72 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 20 x cot 20 = 54.94 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 20 x cosec 20 degrees = 58.47 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 21 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 21 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 189 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 21cot (Π/9))/4 = 2726.18 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 21 x cot 20 = 57.69 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 21 x cosec 20 degrees = 61.39 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 22 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 22 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 198 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 22cot (Π/9))/4 = 2992 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 22 x cot 20 = 60.44 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 22 x cosec 20 degrees = 64.32 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 23 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 23 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 207 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 23cot (Π/9))/4 = 3270.18 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 23 x cot 20 = 63.19 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 23 x cosec 20 degrees = 67.24 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 24 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 24 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 216 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 24cot (Π/9))/4 = 3560.73 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 24 x cot 20 = 65.93 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 24 x cosec 20 degrees = 70.17 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 25 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 25 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 225 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 25cot (Π/9))/4 = 3863.64 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 25 x cot 20 = 68.68 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 25 x cosec 20 degrees = 73.09 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 26 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 26 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 234 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 26cot (Π/9))/4 = 4178.91 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 26 x cot 20 = 71.43 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 26 x cosec 20 degrees = 76.01 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 27 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 27 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 243 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 27cot (Π/9))/4 = 4506.54 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 27 x cot 20 = 74.18 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 27 x cosec 20 degrees = 78.94 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 28 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 28 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 252 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 28cot (Π/9))/4 = 4846.55 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 28 x cot 20 = 76.92 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 28 x cosec 20 degrees = 81.86 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 29 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 29 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 261 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 29cot (Π/9))/4 = 5198.91 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 29 x cot 20 = 79.67 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 29 x cosec 20 degrees = 84.79 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral. 




A regular nonagon where the length of each side is 30 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 9 sides. What are the interior angles and exterior angles? 
If the length of each side is 30 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 9

Perimeter of a nonagon = side x 9 = 270 units

Area of a nonagon = (n x Sidecot (Π/n))/4 = (n x 30cot (Π/9))/4 = 5563.64 square units

Sum of the interior angles of a nonagon = 
 (n-2) x 180 degrees =  (9-2) x 180 degrees = 1260 degrees

Interior Angle of a nonagon = (n-2) x 180/n degrees = (9-2) x 180/9 degrees = 140 degrees 

Exterior angle of a nonagon = 180 - Interior Angle = 180 - 140 = 40 degrees

Inradius = Radius of In-circle = side x cot (Π/9) = 30 x cot 20 = 82.42 units

Circumradius = Radius of Circum-circle = side x cosec (Π/9) = 30 x cosec 20 degrees = 87.71 units

Symmetry Group = D9  9 rotational symmetries and 9 reflection symmetries. The "D" stands for di-hedral.