Ohio Educators Math Exam Practice 2026 – Complete Prep Guide

The vertical line test is a method used to determine if a graph represents a function. A function is defined as a relationship where each input (or x-value) corresponds to exactly one output (or y-value). When performing the vertical line test, if a vertical line intersects the graph at more than one point, it indicates that there are multiple y-values for at least one x-value, which means that the relation does not meet the criteria for being a function. Therefore, passing the vertical line test confirms that for every x-value in the graph, there is only one associated y-value, fulfilling the definition of a function.