Decagon perimeter = 5

The of a decagon is

The perimeter of an decagon is 5. Calculate side, area

Calculate side:
s =P
10

s =5
10

s = 0.5

Calculate Area:
A = 5/2s25 + 2√5
A = 2.5(0.5)2(3.3)
A = 2.5(0.25)(3.3)
A = 5

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