How many lines of symmetry does a regular polygon has? Is there any relation between number of sides and order of rotation of a regular polygon?

A polygon has 14 diagonals. Then, the number of its sides is

A polygon has 54 diagonals , then the number of its sides is :

IF a polygon has 35 diagonals , then the number of sides of the polygon is

If a regular polygon contains 'n' sides then the number of lines of symmetry is ________

A regular polygon of n sides has170 digonals . Then n=

What is the relation between order of rotation and number of lines of symmetry of a geometrical figure?

Draw lines of symmetry for the following figures. Identify which' of them have point symmetry. Is there any relation between lines of symmetry and point symmetry?(pic)