How Many Diagonals does a Decagon have?

Decagon is any polygon with ten sides and ten angles. We can calculate number of diagonals by using simple calculation of n(n-3)/2, where n is the number of sides. In decagon, there are 10 sides, therefore, number of diagonals of decagon = 10(10-3)/2 = 10X7/2 = 5X7 = 35. To find more information click here: