Horizontal Line Test

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This section discusses the Horizontal Line Test

Inverse Functions - Horizontal Line Test

The horizontal line test is a geometric way of knowing if a function has an inverse. See the video below for more details!

1 : The horizontal line test is horizontal because...

It is checking all the outputs for a specific input, which is a horizontal line. It isn’t, it’s a vertical line. It is checking all the inputs for a specific output, which is a horizontal line. It is horizontal because that’s how the test works.