The following activity sheets teach your students to recognize the difference between relations and functions.

How do you recognize and evaluate a math function? When we think about math functions and equations, one thing that immediately comes to mind is the unknown variables. In other words, the evaluation, you'll be doing will reflect on substituting a value to the unknown variable within a formula or function. Moreover, the evaluating equations works extremely well with equations, formulas, and functions have equaled sign in them. Usually, an equation equals another variable whose value is also unknown or a function. Let us find out how Evaluate f(x) = y = 5x - 3, x = 1. Now, you have to place the value of x in the function. f(1) = y = 5(1) - 3, f(1) = y = 5 - 3, f(1) = y = 2 Now, the question was not to find the value of y, because y is dependent on x. In other words, you get the value 2 for y, because the value of x for this function is 1.

Functions are like machines, to a small degree, in that you put something into the machine and the same or an easily predictable product will come out the machine. I like to use the example of a bagel slicer. You know when you put a bagel into the machine, a cut bagel is coming out. Maybe they are not all the same exact bagel, but very predictable. A function in math is just a relationship between a set of inputs and outputs. In this section of worksheets you will first identify functions and then you will complete them. These worksheets explain what a function is and how to solve for one. Your students will also use these worksheets in order to practice identifying relations and functions.

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Print Evaluating Functions Worksheets

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Recognizing and Evaluating Functions Lesson

This worksheet explains how to recognize and evaluate a function. A sample problem is solved, and two practice problems are provided.


Students will determine whether or not an expression is a function, and solve for functions. Ten problems are provided.

Practice Worksheet

Students will learn to manipulate expressions and solve for functions. Ten problems are provided.

Review and Practice

Students review how to recognize functions and take it a step further to evaluate them. Six practice problems are provided.

Evaluating Functions Quiz

Students will demonstrate their proficiency with this skill over the course of the ten problems that are provided.

Class Check

Learn how to substitute values and solve functions in this manner. Three problems are provided, and space is included for students to copy the correct answer when given.