## Elements of Geometry |

### From inside the book

Results 1-5 of 43

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**sides**AC , CB , are in the same straight line . Demonstration . For if CB is not the line AC produced , let CE be ...**number**of straight lines , as CA , CB ( fig . 22 ) , & c . , meet in the same point C , the sum of all the successive ... Page 19

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**number of sides**minus two . Demonstration . Let ABCDE & c . ( fig . 42 ) be the proposed Fig . 42 polygon ; if from the vertex of the angle A we draw to the ver- tices of the opposite angles the diagonals AC , AD , AE , & c . , it is ... Page 32

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**sides**have such a connexion , that when one increases or diminishes in any ratio whatever , the other increases or ...**number**comprehended between O and 1 , and an obtuse angle by a**number**between 1 and 2 . But this manner of expressing ... Page 46

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**number**of linear units contained in the altitude . This measure , however , is not absolute , but relative ; it sup- poses that we estimate , in a similar manner , another rectangle by measuring its**sides**by the same linear unit ; we ... Page 47

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**number**by itself . The squares of the**numbers**1 , 2 , 3 , & c . , are 1 , 4 , 9 , & c . Thus a double line gives a ...**sides**AB , CD . Demonstration . Through the point I , the middle of Of the Proportions of Figures . 47.### Other editions - View all

### Common terms and phrases

ABC fig adjacent angles altitude angle ACB angle BAD base ABCD bisect centre chord circ circular sector circumference circumscribed common cone consequently construction convex surface Corollary cube cylinder Demonstration diagonals diameter draw drawn equal and parallel equiangular equilateral equivalent faces figure four right angles frustum Geom gles greater hence homologous sides hypothenuse inclination inscribed circle isosceles join less let fall line AC manner mean proportional measure the half meet multiplied number of sides oblique lines opposite parallelogram parallelopiped perimeter perpendicular plane MN polyedron prism proposition pyramid S-ABC quadrilateral radii radius ratio rectangle regular polygon right angles right-angled triangle Scholium segment semicircumference side BC similar solid angle sphere spherical polygons spherical triangle square described straight line tangent THEOREM three plane angles triangle ABC triangular prism triangular pyramids vertex vertices whence