## Elements of Geometry and Trigonometry |

### From inside the book

Page 21

...

...

**opposite**C , be greater than AC ,**opposite**B. For , make the angle BCD - B . Then , in the triangle CDB , we shall have CD = BD ( Prop . XII . ) . Now , the side AC < AD + CD ; but AD + CD = C AD + DB AB : therefore ACAB . The greater ...Page 32

...

...

**opposite**sides and angles are equal . Let ABCD be a parallelogram : then will AB = DC , AD = BC , A = C , and ADC ...**opposite**the angle ADB , is equal to the side DC ,**opposite**the equal angle DBC ; and the third sides AD , BC , are ...Page 33

...

...

**opposite**the side AB , is equal to DBC ,**opposite**CD ( Prop . X. ) ; therefore , the side AD is parallel to BC ( Prop . XIX . Cor . 1. ) . For a like reason AB is parallel to CD therefore the quadrilateral ABCD is a parallelogram ...### Contents

Ratios and Proportions | 34 |

The Circle and the Measurement of Angles | 41 |

Problems relating to the First and Third Books | 57 |

14 other sections not shown

### Other editions - View all

### Common terms and phrases

adjacent adjacent angles altitude angle ACB angle BAC ar.-comp base multiplied bisect Book VII centre chord circ circumference circumscribed common cone consequently convex surface Cosine Cotang cylinder diagonal diameter dicular distance divided draw drawn equally distant equations equivalent feet figure find the area formed four right angles frustum given angle given line gles greater homologous sides hypothenuse inscribed circle inscribed polygon intersection less Let ABC logarithm M.
M. Sine number of sides opposite parallelogram parallelopipedon pendicular perimeter perpen perpendicular plane MN polyedron polygon ABCDE PROBLEM Prop proportional PROPOSITION pyramid quadrant quadrilateral quantities radii radius ratio rectangle regular polygon right angled triangle S-ABC Scholium secant segment similar slant height solid angle solid described sphere spherical polygon spherical triangle square described straight line Tang tangent THEOREM triangle ABC triangular prism vertex