## Elements of Geometry and Trigonometry |

### From inside the book

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**rectangle**, which has its angles right an- gles , without having its sides equal . The parallelogram , or rhomboid , which has its opposite sides parallel . The rhombus , or lozenge , which has its sides equal , without having its ... Page 31

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**rectangle**and the square . Cor . 2. The sum of the angles of a pentagon is equal to two right angles multiplied by 5-2 , which amounts to six right angles : hence , when a pentagon is equiangular , each angle is equal to the fifth part ... Page 63

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**rectangle**; if , in addition to this , the sides are equal , it will be a square . PROBLEM XIII . To find the centre of a given circle or arc . Take three points , A , B , C , any where in the circumference , or the arc ; draw AB , BC ... Page 70

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**rectangle**ABGH , which has the same base AB , and the same altitude AH : for the**rectangle**ABGH is equivalent to the parallelogram ABCD ( Prop . I. Cor . ) . Cor . 2. All triangles , which have equal bases and altitudes , are equivalent ... Page 71

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**rectangle**ABCD will contain seven partial**rectangles**, while AEFD will contain four : hence the**rectangle**ABCD is to AEFD as 7 is to 4 , or as AB is to AE . The same reasoning may be applied to any other ratio equally with that of 7 to ...### Other editions - View all

### Common terms and phrases

adjacent adjacent angles altitude angle ACB angle BAC ar.-comp base multiplied bisect Book centre chord circ circumference circumscribed common cone consequently convex surface cosine Cotang cylinder diagonal diameter dicular distance draw drawn equal angles equally distant equiangular equivalent figure formed four right angles frustum given angle given line gles greater homologous sides hypothenuse inscribed polygon intersection less Let ABC let fall logarithm measured by half number of sides oblique lines opposite parallelogram parallelopipedon pendicular perimeter perpen perpendicular plane MN polyedron polygon ABCDE prism produced proportional PROPOSITION pyramid quadrant quadrilateral quantities radii radius ratio rectangle regular polygon right angled triangle S-ABCDE Scholium secant secant line segment side BC similar sine solid angle solid described sphere spherical polygon spherical triangle square described straight line tang tangent THEOREM triangle ABC triangular prism vertex