### Learning Outcomes

By the end of this section, you will be able to:

- Solve rational equations
- Recognize formulas for perimeter, area, and volume
- Recognize the formula that relates distance, rate, and time
- Rearrange formulas to isolate specific variables
- Represent inequalities using an inequality symbol
- Represent inequalities on a number line

In this module, you’ll learn how to use linear equations to model real-world situations and explore several specific types of equations. You’ll also define a process for translating inequalities stated in words and symbols or as graphs on the number line into a special kind of notation called *interval notation*. Before beginning, it will be helpful to refresh techniques for eliminating denominators from rational equations in one variable, and see some formulas that commonly occur during modeling and learn how to manipulate them. A review of representing inequalities using words and symbols and as graphs on the number line is also included in this section.

Warm up for this module by refreshing important concepts and skills you’ll need for success. As you study these review topics, recall that you can also return to Algebra Essentials any time you need to refresh the basics.

### Recall for success

Look for red boxes like this one throughout the text. They’ll show up just in time to give helpful reminders of the math you’ll need, right where you’ll need it.