<P> The common length of the sides equals the radius of the circumscribed circle , which equals 2 3 ( \ displaystyle ( \ tfrac ( 2 ) ( \ sqrt ( 3 ) ) ) ) times the apothem ( radius of the inscribed circle ) . All internal angles are 120 degrees . A regular hexagon has 6 rotational symmetries ( rotational symmetry of order six ) and 6 reflection symmetries ( six lines of symmetry ) , making up the dihedral group D . The longest diagonals of a regular hexagon , connecting diametrically opposite vertices , are twice the length of one side . From this it can be seen that a triangle with a vertex at the center of the regular hexagon and sharing one side with the hexagon is equilateral , and that the regular hexagon can be partitioned into six equilateral triangles . </P>
<P> The common length of the sides equals the radius of the circumscribed circle , which equals 2 3 ( \ displaystyle ( \ tfrac ( 2 ) ( \ sqrt ( 3 ) ) ) ) times the apothem ( radius of the inscribed circle ) . All internal angles are 120 degrees . A regular hexagon has 6 rotational symmetries ( rotational symmetry of order six ) and 6 reflection symmetries ( six lines of symmetry ) , making up the dihedral group D . The longest diagonals of a regular hexagon , connecting diametrically opposite vertices , are twice the length of one side . From this it can be seen that a triangle with a vertex at the center of the regular hexagon and sharing one side with the hexagon is equilateral , and that the regular hexagon can be partitioned into six equilateral triangles . </P>
how many lines of symmetry does hexagon have
how many lines of symmetry does hexagon have
six
six