## Elements of Geometry: Containing the First Six Books of Euclid: With a Supplement ... to which are Added, Elements of Plane and Sphericale Trigonometry ... From the Last London Ed., Enl |

### From inside the book

Results 1-5 of 85

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**third**Book , the re- marks concerning the angles made by a straight line , and the circumference of a circle , are left out , as tending to perplex one who has advanced no farther than the elements of the science . Some propositions ... Page 5

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**third**quantity , are equal to each other . E. A Theorem is a demonstrative proposition ; in which some property is asserted , and the truth of it required to be proved . Thus , when it is said that the sum of the three angles of any ... Page 7

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**third**axiom ; ( 2. Post . ) the second postulate ; ( Def . 3. ) the**third**definition , and so on 29. The word , therefore , or hence , frequently OF GEOMETRY . BOOK I. Page 13

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**third**sides , shall be equal ; and the areas of the triangles shall be equal ; and their other angles shall be equal , each to - each , viz . those to which the equal sides are oppos ̊te . * D Let ABC , DEF be two triangles which have ... Page 22

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**third**side . Let ABC be a triangle ; any two sides of it together are greater than the**third**side , viz . the sides BA , AC greater than the side BC ; and AB , BC greater than AC ; and BC , CA greater than AB . Produce BA to the point D ...### Other editions - View all

### Common terms and phrases

ABC is equal ABCD adjacent angles altitude angle ABC angle ACB angle BAC base BC bisected centre chord circle ABC circumference cosine cylinder demonstrated described diameter divided draw equal and similar equal angles equiangular equilateral equilateral polygon equimultiples Euclid exterior angle fore four right angles given rectilineal given straight line greater Hence hypotenuse inscribed join less Let ABC Let the straight magnitudes meet multiple opposite angle parallel parallelogram parallelopiped perpendicular polygon prism PROB PROP proportional proposition quadrilateral radius ratio rectangle contained rectilineal figure remaining angle right angled triangle SCHOLIUM segment semicircle shewn side BC sine solid angle solid parallelopiped spherical angle spherical triangle square straight line BC THEOR touches the circle triangle ABC triangle DEF wherefore