Answer:
(a) (1,5)
(b) Every subset of a cartesian product is a relation, therefore this is a relation.
(c) The relation IS NOT a function.
Explanation:
(a)
(1,5)
Notice that 3(1) +1 = 4 < 5 therefore (1,5) is an order pair that satisfies the equation.
(b)
Every subset of a cartesian product is a relation, therefore this is a relation.
(b)
A relation is a function of the following condition holds
if (a,b) and (c,b) belong to the relation then (a=c)
In this case, (1,5), (0,5) belong to the relation but 0 is different than 5, therefore the relation IS NOT a function.