Before this we do this question let's get fimiliar with what's a function.
A function is a equation that when graphed, each input(x) correspond to one output(y). This means one inputs can't map to the diffrent output.
The vertical line test is just puting a vertical line anywhere on the function. If the vertical line touches more than two points your graph is not a function. If it touches one you graph is a function. The reason is because a vertical line that touches 2 points means one x maps to two diffrent y and thats not a function.
In conclusion the graph does pass the vertical line test so it is a function.
