There are multiple technical ways to explain this but the best one that works for me is the "vertical line test" can be used to find a function or non function. All you have to do is position your pencil vertically, place it to the far left of the graph drag it horizontally across to the right side of the graph. If your pencil is making contact with two lines at one time, it is NOT a function. Hopefully this makes sense.
The graph is done using Desmos. Just by substitution x = 1 will force the graph to go to y = 0, but graphs are not always that good. This one gets 1.111
to get y = 0. I'd use 1 if you had to answer it and a computer will mark it.
