Answer
vertical;
horizontal
Work Step by Step
The vertical line test is used to tell whether graphs are graphs of functions. The horizontal line test is used whether a graph of a function is one-to-one.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.