Did you get the rigging along with it? That would make it easier to identify.
Search Sailboatdata.com by length and then start looking at photos. It isn't a Hobie 405 or Ghost 13, I'm not going to go look at the rest of the possible hits. The fact that the mast appears to be deck stepped is unusual.
Dale: dinghies can be sailboats. Not all dinghies are inflatable tenders.