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FUNCTIONS - Identifying Functions from Graphs

FUNCTIONS - Identifying Functions from Graphs

Author: Kate Sidlo

At the end of this tutorial students should be able to use the vertical line test to test if a graph is a function.

Students should be able to explain why the vertical line test works using the definition of a function and/or the code example.

In this tutorial students are introduced to the concept of the vertical line test and how to check if a graph is a function.

The metaphor of a coding grid as a good and bad code as well as good and bad functions is used throughout.

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1) Take notes from the podcast

2) Add new definitions from the vocabulary section to your vocabulary sheet

FUNCTIONS - Identifying Functions from Graphs


FUNCTION: A relationship where every input has one and only one output

INPUT: A term or number that is plugged into a relationship; the x-variable in an ordered pair

RELATIONSHIP: A comparison of terms, variables, and/or numbers (typically an equation or inequality)

OUTPUT: A term or number that is the answer or solution to a relationship; the y-variable in an ordered pair

VERTICAL LINE TEST: A test that uses vertical lines to check if a graph is a function.  Each vertical line can intersect a graph only once for a graph to be a function.