Answer:
C) {(12,3), (11,2), (10,1), (9,0), (8,1), (7,2), (6,3)} Is a function.
Step-by-step explanation:
The easiest way to tell if a Relation is a Function (in my opinion) is the Verticle Line test. Use your pairs and put them in a graph. Then connect the dots, and if your line at any point touches the graph once, then your Relation is a Function. If it touches the graph more than once, it is not a Function.
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