Answer:
Not a function
Step-by-step explanation:
To answer this, we first need to know what a function actually is: A function is a relation between 2 sets which relates the element of the first set to only one element of the second set.
We can see in the provided image that the value -9 is related to 2 values of the second set, hence it is NOT a set.
Another way to think about it is that a function takes an input and gives only one output (where the left set is the input and the right set is the output). Since -9 gives 2 outputs from the given relation, it cannot be a function.
