Introduction to Solving Equations Using the Subtraction and Addition Properties of Equality

What you’ll learn to do: Solve equations using the subtraction and addition properties of equality

An image of a calder mobile is shown. It has several black and red geometric shapes hanging down.

A Calder mobile is balanced and has several elements on each side.

Teetering high above the floor, this amazing mobile remains aloft thanks to its carefully balanced mass. Any shift in either direction could cause the mobile to become lopsided, or even crash downward. In this chapter, we will solve equations by keeping quantities on both sides of an equal sign in perfect balance.

Before you get started in this module, try a few practice problems and review prior concepts.

Readiness Quiz



If you missed these problems, review the video below.



If you missed these problems, watch the video below for a reminder.

We are now ready to “get to the good stuff.” You have the basics down and are ready to begin one of the most important topics in algebra – solving equations. The applications are limitless and extend to all careers and fields. Also, the skills and techniques you learn here will help improve your critical thinking and problem-solving skills. This is a great benefit of studying mathematics and will be useful in your life in ways you may not see right now.