How many lines of symmetry does a polygon has?

Answer 1

A polygon need not have any lines of symmetry. The maximum number of lines of symmetry is attained if the polygon is regular; and this is the number of sides (or vertices) of the polygon. If a regular polygon has an even number of sides, then the lines of symmetry are those joining opposite vertices, and those joining the mid-points of opposite sides. If the polygon has an odd number of sides/vertices, the lines of symmetry are those joining each vertex to the mid-point of the opposite side.