Final answer:
A function is a mathematical relationship between two sets of values, and in this case, the given set is a function with a domain of {1, 3, 4, 5, 6} and a range of {3, 4, 5, -7}.
Step-by-step explanation:
A function is a mathematical relationship between two sets of values in which each value in the input set is associated with exactly one value in the output set. In the given set A={(1, 3), (3, 4), (4, 5), (5,5), (6, -7)}, we can see that each input value is associated with exactly one output value, satisfying the criteria for a function.
The domain of a function is the set of all possible input values. In this case, the domain is {1, 3, 4, 5, 6}.
The range of a function is the set of all possible output values. In this case, the range is {3, 4, 5, -7}.