Question

When given a graph, the vertical line test can be used to determine functionality. Describe the vertical line test and explain the reasons why a graph would, or would not, represent a function.

Answer 1

When given a graph, the vertical line test can be used to determine functionality. The vertical line test would represent a function if no more than one point of the graph of a relation, this shows that only one output value for each input value. If this doesn't apply or more than one point is on the line then it would not represent a function.

Explanation:

Draw vertical lines to intersect on a graph.

The relation is a function if there’s only one point of intersection on a graph.

The relation is not a function if there’s more than one point of intersection on a graph.

The vertical line test is used to determine if each input has exactly one output.

Answer 2

The vertical line test is a way for you to see if a graph represents a function. It allows you to identify if any x values have more than one y value.

A graph would be a function if every input (x) has exactly one output (y). A graph would not be a function if an input (x) has more than one output (y).

Explanation:

In a function, every input within the domain of the function must have exactly one output. If the graph has an input that has more than one output, then it is not a function. The vertical line test is what allows you to see if a graph is a function or not.