## Elements of Geometry |

### From inside the book

Results 1-5 of 94

Page iii

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**plane**figures , and the other of solids ; and the subdivisions of each part are denominated sections . As a knowledge of algebraical signs and the theory of propor- tions is necessary to the understanding of this treatise , a brief ... Page vi

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**plane**geometry , and four of solid geometry . The first section , entitled first principles , & c . contains the prop- erties of straight lines which meet those of perpendiculars , the theorem upon the sum of the angles of a triangle ... Page vii

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**planes**and of solid angles . This part is very necessary for the understanding of solids , and of figures in which different**planes**are considered . We have endeavoured to render it more clear and more rigorous than it is in common ... Page 1

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**plane**, nor composed of**planes**, is a curved surface . 8. A solid is that which unites the three dimensions of ex- ension . 9. When two straight lines AB , AC , ( fig . 2 , ) meet , the quan- Fig . 2 . tity , whether greater or less ... Page 2

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**plane**, and produced ever so far both ways , they do not meet . 13. A**plane**figure is a**plane**terminated on all sides by lines . If the lines are straight , the space which they contain is called a rectilineal figure , or polygon ( fig ...### Other editions - View all

### Common terms and phrases

ABC fig adjacent angles altitude angle ACB angle BAC 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 angles equiangular equilateral equivalent faces figure formed four right angles frustum GEOM given point gles greater hence homologous sides hypothenuse inclination intersection isosceles triangle JOHN CRERAR LIBRARY join less Let ABC let fall line AC mean proportional measure the half meet multiplied number of sides oblique lines opposite parallelogram parallelopiped perimeter perpendicular plane MN polyedron prism produced proposition radii radius ratio rectangle regular polygon right angles Scholium sector segment semicircle semicircumference side BC similar solid angle sphere spherical polygons spherical triangle square described straight line tangent THEOREM three angles triangle ABC triangular prism triangular pyramids vertex vertices whence