1. The problem statement, all variables and given/known data The group of symmetries of a regular pentagram is isomorphic to the dihedral group of order 10. Show that this is true. 3. The attempt at a solution It seems to me that the group shown by the "star" has order 5, since, by following the lines from one point, it takes 5 total paths to get back to the original point. So I thought it would isomorphic to the cyclic group of order 5.....how is it isomorphic to the dihedral group?