Number of quadrilaterals which can be constructed by joining the vertices of a convex polygon of 20 sides if none of the side of the polygon is also the side of the quadrilateral is

How many quadrilaterals can be formed joining the vertices of a convex polygon of n sides?

Find the number of diagonals by joining the vertices of a polygon of n sides.

Consider a polygon of sides 'n' which satisfies the equation 3*^(n)P_(4)=^(n-1)P_(5) . Q. Number of quadrilaterals thatn can be formed using the vertices of a polygon of sides 'n' if exactly 1 side of the quadrilateral in common with side of the n-gon, is

Find the number of diagonals that can be drawn by joining the angular points of a a polygon of 20 sides.

Consider a polygon of sides 'n' which satisfies the equation 3*.^(n)P_(4)=.^(n-1)P_(5) . Q. Number of quadrilaterals that can be made using the vertices of the polygon of sides 'n' if exactly two adjacent sides of the quadrilateral are common to the sides of the n-gon is

Find the number of triangles which can be formed having vertices at angular points of a convex polygon of m sides.

Find the numbers of diagonals in the polygon of n sides.

Find the number of diagonals in the convex polygon of n sides .

The number of diagonals of a polygon of 20 of sides

The number of diagonals of a polygon of 15 sides is: