Question

What is the vertical line test and how is it used​

Answer 1

A vertical line is a line that passes through no more than one point. Means only one point in one of the lines. The picture is an example :)

Answer 2

The vertical line test is used to determine if a graph of a relationship is a function or not. if you can draw any vertical line that intersects more than one point on the relationship, then it is not a function.