Question 309582
a relation is a function if there is only one solution for each domain member, that means no repeating value of a domain member in a solution set. A domain member is the left part of the coordinate system, a solution for the domain member is the right part of the coordinate system.
Example: {(1, 2), (1, 4), (2, 5)} in not a function since a domain member, that is 1 have more than one solution, 2 and 4


so, if we have {(3, 6),(4, 6),(10, 6),(12, 6)}
it is a function, because there aren't any domain members that have more than one solution (the domain members are 3, 4, 10, and 12)