Question

Is the following relation a function?

x y
1 −2
1 −3
2 1
3 −2

Answer 1

It is not a function!

Explanation:

It is not a function!

A function can't have two y-values assigned to the same x-value. In this case, you can se that for x=1 we have two y-values, which are y= -2 and y= -3.

We can have have two x-values assigned to the same y-value, that's why it's okay that for x=1 and x=3 we have the same y-value y=-2