Let T be the set of all movie actors and actresses For x y e
     Let T be the set of all movie actors and actresses. For x, y elementof T, define x R y if there is some movie that both x and y appear in. Which properties of equivalence relations does R satisfy? The relation  reflexive, because every actor/actress  in a movie with  The relation  symmetric, because if a has been in a movie with b then b  in a movie with The relation  transitive, because a could appear with b in a movie, b could appear in another movie with c, and that  guarantee that a will appear in a movie with   
  
  Solution
In mathematics, an equivalence relation is a binary relation that is at the same time a reflexive relation, a symmetric relation and atransitive relation. As a consequence of these properties an equivalence relation provides a partition of a set into equivalence classes
1.the relation is reflexive because every actor work in a movie with X,Y
2.the relation is symmetric if a has been in a movie with b ,then b has been in a movie with a
3.the relation is transitive ................and that B guarantee that a will appear in a movie with C

