A regular hexagon with six equal sides has six lines of symmetry. For all regular polygons, the number of lines of symmetry is equal to the number of sides.
For regular polygons with an odd number of sides, each line of symmetry bisects one angle and the side opposite. For regular polygons with an even number of sides, the lines of symmetry alternate between bisecting opposite angles, and bisecting opposite sides. It is possible to construct irregular polygons that are symmetrical, but no irregular polygon can have as many lines of symmetry as a regular polygon with the same number of sides.