How do functions connect elements of their domain to elements of their range?

Step-by-step explanation:

Each element of the domain connects to no more than ONE element of the range. More than one such connection indicates a relation, not a function.

All of the values that can go into a relation or function (input) are called the domain. The domain is the set of all first elements of ordered pairs (x-coordinates). The range is the set of all second elements of ordered pairs (y-coordinates). Only the elements "used" by the relation or function constitute the range.