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A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 30 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 2cot (Π/15))/4 = 70.56 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 2 x cot 12 = 9.4 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 2 x cosec 12 degrees = 9.61 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 45 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 3cot (Π/15))/4 = 158.78 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 3 x cot 12 = 14.11 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 3 x cosec 12 degrees = 14.42 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 60 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 4cot (Π/15))/4 = 282.27 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 4 x cot 12 = 18.81 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 4 x cosec 12 degrees = 19.23 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 75 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 5cot (Π/15))/4 = 441.05 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 5 x cot 12 = 23.52 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 5 x cosec 12 degrees = 24.04 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 90 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 6cot (Π/15))/4 = 635.12 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 6 x cot 12 = 28.22 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 6 x cosec 12 degrees = 28.85 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 105 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 7cot (Π/15))/4 = 864.47 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 7 x cot 12 = 32.93 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 7 x cosec 12 degrees = 33.66 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 120 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 8cot (Π/15))/4 = 1129.11 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 8 x cot 12 = 37.63 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 8 x cosec 12 degrees = 38.47 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 135 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 9cot (Π/15))/4 = 1429.03 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 9 x cot 12 = 42.34 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 9 x cosec 12 degrees = 43.28 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 150 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 10cot (Π/15))/4 = 1764.23 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 10 x cot 12 = 47.04 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 10 x cosec 12 degrees = 48.09 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 165 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 11cot (Π/15))/4 = 2134.72 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 11 x cot 12 = 51.75 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 11 x cosec 12 degrees = 52.9 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 180 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 12cot (Π/15))/4 = 2540.5 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 12 x cot 12 = 56.45 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 12 x cosec 12 degrees = 57.71 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 195 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 13cot (Π/15))/4 = 2981.55 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 13 x cot 12 = 61.16 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 13 x cosec 12 degrees = 62.52 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 210 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 14cot (Π/15))/4 = 3457.9 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 14 x cot 12 = 65.86 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 14 x cosec 12 degrees = 67.33 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 225 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 15cot (Π/15))/4 = 3969.53 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 15 x cot 12 = 70.56 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 15 x cosec 12 degrees = 72.14 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 240 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 16cot (Π/15))/4 = 4516.44 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 16 x cot 12 = 75.27 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 16 x cosec 12 degrees = 76.95 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 255 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 17cot (Π/15))/4 = 5098.64 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 17 x cot 12 = 79.97 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 17 x cosec 12 degrees = 81.76 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 270 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 18cot (Π/15))/4 = 5716.12 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 18 x cot 12 = 84.68 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 18 x cosec 12 degrees = 86.57 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 285 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 19cot (Π/15))/4 = 6368.89 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 19 x cot 12 = 89.38 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 19 x cosec 12 degrees = 91.38 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 300 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 20cot (Π/15))/4 = 7056.94 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 20 x cot 12 = 94.09 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 20 x cosec 12 degrees = 96.19 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 315 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 21cot (Π/15))/4 = 7780.28 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 21 x cot 12 = 98.79 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 21 x cosec 12 degrees = 101 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 330 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 22cot (Π/15))/4 = 8538.9 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 22 x cot 12 = 103.5 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 22 x cosec 12 degrees = 105.81 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 345 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 23cot (Π/15))/4 = 9332.8 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 23 x cot 12 = 108.2 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 23 x cosec 12 degrees = 110.62 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 360 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 24cot (Π/15))/4 = 10162 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 24 x cot 12 = 112.91 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 24 x cosec 12 degrees = 115.43 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 375 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 25cot (Π/15))/4 = 11026.47 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 25 x cot 12 = 117.61 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 25 x cosec 12 degrees = 120.24 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 390 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 26cot (Π/15))/4 = 11926.23 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 26 x cot 12 = 122.32 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 26 x cosec 12 degrees = 125.05 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 405 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 27cot (Π/15))/4 = 12861.28 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 27 x cot 12 = 127.02 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 27 x cosec 12 degrees = 129.86 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 420 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 28cot (Π/15))/4 = 13831.61 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 28 x cot 12 = 131.72 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 28 x cosec 12 degrees = 134.67 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 435 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 29cot (Π/15))/4 = 14837.22 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 29 x cot 12 = 136.43 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 29 x cosec 12 degrees = 139.48 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral. 




A regular Pentadecagon 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 15 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 = 15

Perimeter of a Pentadecagon = side x 15 = 450 units

Area of a Pentadecagon = (n x Sidecot (Π/n))/4 = (n x 30cot (Π/15))/4 = 15878.12 square units

Sum of the interior angles of a Pentadecagon = 
 (n-2) x 180 degrees =  (15-2) x 180 degrees = 2340 degrees

Interior Angle of a Pentadecagon = (n-2) x 180/n degrees = (15-2) x 180/15 degrees = 156 degrees 

Exterior angle of a Pentadecagon = 180 - Interior Angle = 180 - 156 = 24 degrees

Inradius = Radius of In-circle = side x cot (Π/15) = 30 x cot 12 = 141.13 units

Circumradius = Radius of Circum-circle = side x cosec (Π/15) = 30 x cosec 12 degrees = 144.29 units

Symmetry Group = D15  15 rotational symmetries and 15 reflection symmetries. The "D" stands for di-hedral.