Question

Is {(4, 8), (8, 4), (4, 12), (20, 16), (12, 16)} a function

Answer 1

no

Explanation:

Look at the first numbers of each ordered pair:

4, 8, 4, 20, 12

If any are repeated, the relation is NOT a function. Here, 4 is repeated.

The relation is not a function.