Question

Is this graph a function?

Answer 1

No.

To check if a graph is a function, make sure there is exactly one y value for every x value. To find this, pretend you are moving a vertical line across the entire graph. As long as it stays straight up and down, it should only touch the line in one place.

For example, put an imaginary vertical line at the x value of -4. There are 3 different places the lines touch, so this graph doesn’t represent a function.