Decagon area = 16

The of a decagon is

The area of an decagon is 16. Calculate side, perimeter

Calculate side:
A = 5/2s25 + 2√5
A = 2.5s2(3.3)
s2 =2 x A
5 x 3.3

s2 =2 x 16
5 x 3.3

s2 =32
15.

s2 = 2.6
s = √2.6
s = 3

Calculate Perimeter:
P = 10 x side
P = 10 x 3
P = 14.

Calculate Sum of the Interior Angles:
Interior Angle Sum = (sides - 2) x 180°
Interior Angle Sum = (10 - 2) x 180°
Interior Angle Sum = 8 x 180°
Interior Angle sum = 1440°

Calculate the number of diagonals of the polygon:
Diagonals =n(n - 3)
2

Diagonals =10(10 - 3)
2

Diagonals =10(7)
2

Diagonals =70
2

Diagonals = 35

Calculate the number of diagonals from one vertex:
1 vertex Diagonals = n - 3
1 vertex Diagonals = 10 - 3
1 vertex Diagonals = 7

Calculate the number of triangles that can be drawn from one vertex:
Triangles = N - 2
Triangles = 10 - 2
Triangles = 8