THE
GUIDE TO
ALGEBRA
Dear Reader,
I first heard the joke Q: Define aftermath. A: Algebra. very early in my teaching career, when the only people who studied elementary algebra were the college-bound students, and the only ones likely to take intermediate algebra were those who were headed toward physics, engineering, or mathematics.
The times have changed. Since the introduction of the scientific calculator, the personal computer, and the graphing calculator, the changes in educational expectations have become much more intense. The PC did not quite live up to its claim that users would have more free time. Instead, the amount of data that was available to the general public grew exponentially. Employers expected that more of their employees would access and analyze the data. With this increase in expectations came a significant increase in the number of students taking more than elementary algebra.
You will find that this book uses the graphing calculator with some regularity. This text also contains traditional symbol manipulation, because these skills are the building blocks for more advanced topics.
I hope that this book helps you better understand some of these basic principles of algebra and that you enjoy working through the material.
Chris Monahan
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THE
GUIDE TO
ALGEBRA
A step-by-step guide to the basics
of algebrain plain English!
Christopher Monahan
Former President, Association of Mathematics Teachers of New York State
To my family
dht, kem-s, rmm-s, kmm, art, bht, sast, and crt
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Contents
Acknowledgments
The material and examples used in this book are drawn from the interaction with the thousands of students who sat in my classes every day for more than thirty years. I thank you for all you taught me about teaching, and I hope this book makes you proud.
Thanks go to Dave Bock, who put me in contact with my agent, Grace Freedson. I also must thank Lisa Laing for her expertise in editing this text and Matt LeBlanc for his advice on the graphics. I especially want to thank my wife Diane. Without her support and encouragement, this book would not have been written.
Top 10 Reasons WhyAnd How
You Should Study Algebra
Mathematicians Are The Original Texters. There Really Is No Difference Between Using Statements Like Lol And Bff To Save Space And Using x For The Number That Is Unknown. DonT Let The Use Of Symbols Scare You.
Mathematics Is Not As Rigid As People Think. There Are Many Ways To Solve Problems. Algebraic, Graphical, And Tabular Approaches Are Often Equally Good Options For Getting To The Answer.
Algebra Has Many Applications Outside Of The Mathematics Classroom.
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