Answer:

Explanation:
Given relation:
{(6,-1), (-4, 2), (5, 2), (4, 6), (6,5)}
For a relation to be a function, the domain (x-values) should NOT repeat values.
Here,
Domain = {6, -4, 5, 4, 6}
The number 6 in domain is repeated. Hence, this relation is not a function.
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