Decide whether the relation is a function and give the 31 18
     Decide whether the relation is a function, and give the  {(3,1), (18, -6), (33, 1), (3, 0), (47, 0)}  The domain is {3, 18, 33, 47}.  (Use a comma to separate answer as needed.  The range is {-6, 0, 1}.  (Use a comma to separate answer as needed.  Type  is relation a function? 
  
  Solution
A function is always a relation. You always have f(x) = something in terms of x. f(x) representing y, it is always a relation between x and y. However, the other way around is not always true. A relation is not always a function. It could be a function if it associates for every y, one and only one something in terms of x.
In the given problem 3 is having two images 1 and 0 i.e., (3,1),(3,0)
so the given one is not a function

