Contents

Translator’s Preface ix

Author’s Prefaces xi

Preface to the Second Edition xi

Preface to the Eighth Edition xii

Preface to the Twelfth Edition xii

Preface to the First Edition xii

Introduction 1

Book I

On the Straight Line 7

Chapter I. On Angles 9

Exercises 18

Chapter II. On Triangles 21

Exercises 29

Chapter III. Perpendiculars and Oblique Line Segments 31

Exercises 33

Chapter IV. Cases of Congruence for Right Triangles.

A Property of the Bisector of an Angle 35

Exercises 37

Chapter V. Parallel Lines 39

Exercises 44

Chapter VI. On Parallelograms. — On Translations 45

Exercises 51

Chapter VII. Congruent Lines in a Triangle 53

Exercises 56

Problems for Book 1 57

Book II

On the Circle 59

Chapter I. Intersection of a Line with a Circle 61

Exercises 64

Chapter II. Diameters and Chords 65

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