Algebra II Workbook For Dummies, 2nd Edition

Chapter 14

Getting Squared Away with Matrices

In This Chapter

Enter the matrix: Understanding arrays of numbers

Performing simple operations on matrices

Multiplying one matrix by another

Working with identity matrices (and a sweet shortcut) to find inverses

Using matrix inverses to solve systems of equations

In algebra, a matrix is a rectangular array of numbers, not a revolution or something reloaded such as the computer-generated universe inhabited by Keanu Reeves. An array of numbers is a quick, down-and-dirty way of expressing a lot of information without going into a lot of detail. In the real world, matrices are a way of organizing business elements or transportation capabilities into a format that you can operate on and analyze.

In this chapter, you add, subtract, multiply, and divide (well, sort of divide) matrices — when allowed. I cover the rules governing operations on matrices. People also use matrices to solve large systems of linear equations with ease and efficiency, ...