Understanding Algebra

An online algebra text by James W. Brennan

Book Contents

Chapter 1- The Numbers of Arithmetic

  • The Real Number System
  • Addition and Subtraction of Real Numbers
  • Multiplication and Division
  • Positive Integer Exponents
  • Order of Operations
  • Fractions
  • Percents
  • Decimals
  • Properties of Real Numbers
  • Chapter 2- Introduction to Algebra
  • Algebraic Expressions
  • Simplifying Algebraic Expressions
  • Solutions of Algebraic Equations
  • Addition Principle
  • Multiplication Principle
  • Using the Principles Together
  • Chapter 3- Word Problems
  • Problem Solving Strategies
  • Words for Operations
  • General Word Problems
  • Chapter 4- Graphing and Straight Lines
  • Rectangular Coordinates
  • Graphing Functions
  • Straight Lines
  • Chapter 5- Systems of Linear Equations
  • The Solutions of a System of Equations
  • Addition Method
  • Substitution Method
  • Chapter 6- Polynomials
  • Polynomials
  • Addition and Subtraction of Polynomials
  • Multiplication of Polynomials
  • Special Products of Binomials
  • Factoring Polynomials
  • Factoring a Quadratic Trinomial by Grouping
  • Summary of Steps to Factor Quadratic Trinomials
  • Chapter 7- Rational Expressions
  • Rational Expressions
  • Simplifying Rational Expressions
  • Chapter 8- Exponents and Roots
  • Exponents
  • Roots
  • Simplifying Radical Expressions
  • Rationalizing the Denominator
  • Chapter 9- Quadratic Equations
  • Quadratic Equations 
  • Solving by Square Roots
  • Solving by Factoring
  • Completing the Square
  • The Quadratic Formula
  • The complete contents of this algebra textbook are available here online. This text is suitable for high-school Algebra I, preparing for the GED, a refresher for college students who need help preparing for college-level mathematics, or for anyone who wants to learn introductory algebra. I am especially pleased to help homeschoolers.

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    Graphing Applet (Java applet for exploring slope and intercepts of straight lines)


    Prime Factorization Machine


    Prime Number List


    Quadratic Equation Solver/Plotter



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