For this case we have that by definition, for a relation to be a function, each one of the elements of the output set, represented by "x", must be related to a single arrival set element, represented by "y". That is, there must be uniqueness.
In addition, it must be fulfilled that all the elements of the output set are related to some element of the arrival set. That is, there must be existence.
In the figure it is observed that each element of the first set is related to a single element of the second set, besides all the output elements are related,
So, the given relationship is a function.
Answer:
If it is a function