Question

Choose the best description of the relation shown below:

A. The relation is a function because every input has exactly one output
B. The relation is a function because every output has exactly one input
C. The relation is not a function because every input is different.
D. It is impossible to tell if the relation is a function without knowing more coordinates

Answer 1

There is a rule:

One input(x-value) can only have one output(y-value) in order to be a function.

If one input has more than one output, it is not a function.

(This doesn't apply to outputs, one output can have more than one input and still be a function)

(2,10),(4,15),(6,20),(8,25)

This is a function because each input only has one output.

Your answer is A