General Idea:
Vertical line test is a test used to determine if a relation is a function. As per vertical line test, a relation is a function if there are no vertical lines that intersect the graph at more than one point.
Applying the concept:
Kelly ask Tyrese to help her use the vertical line test to determine whether or not the curve that she was given it is a function Tyrese informed Kelly that an order for the given curve to be designated as a function of a vertical line drawn through any x value must intersect the Curve [tex] ONE [/tex] time.