# Functions

### Popular Tutorials in Functions

#### What's a Function?

Function rules are like instructions on how to change input values into their respective output values. In this tutorial, see how to write a function rule for a given relation. Check it out!

#### How Can You Tell if a Relation is Not a Function?

Every function is a relation, but not every relation is a function! Watch this video to learn how to tell which relations are functions and which are not.

#### How Do You Graph a Linear Equation From a Table?

A table of values for a linear equation can be very helpful, but a graph of the equation can be even better! In this tutorial, you'll see how to use a table of values to graph a linear equation!

#### How is a Function Defined?

You can't go through algebra without learning about functions. This tutorial shows you the definition of a function and gives you an example of a function. Take a look!

#### How Do You Make an Approximate Graph From a Word Problem?

Sometimes a word problem describes a situation that can be better understood if it were graphed. This tutorial gives an example of one such word problem. Check it out!

#### How Do You Solve a Word Problem Using a Function?

Word problems are a great way to see math in action! This word problem deals with calculating profit after a certain number of years. See how to use a function from the word problem to solve!

#### How Do You Figure Out If a Relation is a Function?

How do you figure out if a relation is a function? You could set up the relation as a table of ordered pairs. Then, test to see if each element in the domain is matched with exactly one element in the range. If so, you have a function! Watch this tutorial to see how you can determine if a relation is a function.

#### How Do You Use the Vertical Line Test to Figure Out if a Graph is a Function?

Trying to figure out if an equation is a function? Graph it and perform the vertical line test. If it passes, then it's a function! Get some practice by watching this tutorial!

#### How Do You Find f(x) If You Have a Value For x?

To solve a function for a given value, plug that value into the function and simplify. See this first-hand by watching this tutorial!

#### What's a Function?

You can't go through algebra without learning about functions. This tutorial shows you a great approach to thinking about functions! Learn the definition of a function and see the different ways functions can be represented. Take a look!

#### What's the Vertical Line Test?

Even graphs need to worry about tests! Using the vertical line test, you can figure out if a graph is a function or not. Watch this tutorial and learn about the vertical line test. Then, put your graphs to the test!

#### What is Function Notation?

Every see 'f(x)' in your math? That's function notation! It's a way to indicate that an equation is a function. Learn about function notation by watching this tutorial.

#### What is a Continuous Function?

You've probably seen a continuous function before and not even known it! In this tutorial, you'll learn what a continuous function is and what a graph needs to have in order to be continuous.

#### How Can You Tell if a Function is Linear or Nonlinear From a Table?

To see if a table of values represents a linear function, check to see if there's a constant rate of change. If there is, you're looking at a linear function! This tutorial shows you how to tell if a table of values represents a linear function.