Why isn't a vertical line a function? What test rules it out?

If you draw any vertical line and it intersects more than one point on the relationship, it isn’t a function. The test is called the vertical line test. Hope this helps.

Step-by-step explanation:

Step-by-step explanation:

If you look at it this way, one can say that algebra does act as a tool to improve communication in the sense that, it is similar, in a way, to learning a new language. You don't rush into it, you start rather gently, little by little, step by step before you can say, you fully get it. We can then agree that this will improve one's communication prowess because the person would be learning something new with the help of some other people.