Sonal Bhatt - Idiots Guides: Geometry

No one likes a know-it-all. Most of us realize theres no such thinghow could there be? The world is far too complicated for someone to understand everything there is to know. So when you come across a know-it-all, you smile to yourself as they ramble on because you know better.

You understand that the quest for knowledge is a never-ending one, and youre okay with that. You have no desire to know everything, just the next thing. You know what you dont know, youre confident enough to admit it, and youre motivated to do something about it.

At Idiots Guides, we, too, know what we dont know, and we make it our business to find out. We find really smart people who are experts in their fields and then we roll up our sleeves and get to work, asking lots of questions and thinking long and hard about how best to pass along their knowledge to you in the easiest, most-accessible way possible.

After all, thats our promiseto make whatever you want to learn As Easy as It Gets. That means giving you a well-organized design that seamlessly and effortlessly guides you from page to page, topic to topic. It means controlling the pace youre asked to absorb new informationnot too much at once but just what you need to know right now. It means giving you a clear progression from easy to more difficult. It means giving you more instructional steps wherever necessary to really explain the details. And it means giving you fewer words and more illustrations wherever its better to show rather than tell.

So here you are, at the start of something new. The next chapter in your quest. It can be an intimidating place to be, but youve been here before and so have we. Clear your mind and turn the page. By the end of this book, you wont be a know-it-all, but your world will be a little less complicated than it was before. And well be sure your journey is as easy as it gets.

Mike Sanders
Publisher, Idiots Guides

To Sonals mom, Gita, and Rebeccas mom, Bernadette.

ALPHA BOOKS

Published by Penguin Group (USA) Inc.

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IDIOTS GUIDES and Design are trademarks of Penguin Group (USA) Inc.

International Standard Book Number: 978-1-61564-523-7
Library of Congress Catalog Card Number: 2013957749

16 15 14 8 7 6 5 4 3 2 1

Interpretation of the printing code: The rightmost number of the first series of numbers is the year of the books printing; the rightmost number of the second series of numbers is the number of the books printing. For example, a printing code of 14-1 shows that the first printing occurred in 2014.

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Note: This publication contains the opinions and ideas of its author. It is intended to provide helpful and informative material on the subject matter covered. It is sold with the understanding that the author and publisher are not engaged in rendering professional services in the book. If the reader requires personal assistance or advice, a competent professional should be consulted.

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Publisher:Mike Sanders

Executive Managing Editor:Billy Fields

Senior Acquisitions Editor:Tom Stevens

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Cover Designer:Laura Merriman

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Introduction

Geometry requires a great deal of spatial sense. The ability to imagine figures in varied dimensions and transform these figures is not easy for all. Geometry also requires logical reasoning. The ability to use definitions and properties to validate conclusions can be a daunting task. As you sit in class or work on geometry problems, you may feel lost in the forest with no end in sight. Definitions sound like birds chirping and examples appear to be monkeys swinging from tree to tree. Dont worry, you are not alone!

We all have strengths and areas in need of improvement. What can help you through is perseverance and the right resourcefor you, its Idiots Guides: Geometry.

In this book, we have presented geometry through illustrated examples and provided helpful hints to make geometry easy to understand. So rather than paying a personal tutor loads of money, let this book guide your way home through the forest of geometry!

How This Book Is Organized

This book is presented in seven parts:

In , The Foundations of Geometry, you will learn about all the basic elements of geometry. You will define, identify, and name points, lines, planes, and angles. You will also learn about the relationships formed between lines and angles and how to find their measures.