# An Elementary Geometry

Thompson, Bigelow, & Brown, 1873 - Geometry - 110 pages

### Contents

 GEOMETRY 1 RATIO AND PROPORTION 25 BOOK II 31
 BOOK III 49 BOOK IV 64 PROBLEMS OF CONSTRUCTION 89

### Popular passages

Page 107 - To describe an isosceles triangle, having each of the angles at the base double of the third angle.
Page 5 - If, at a point in a straight line, two other straight lines, upon the opposite sides of it, make the adjacent angles together equal to two right angles, these two straight lines shall be in one and the same straight line.
Page 25 - Four quantities are in proportion when the ratio of the first to the second is equal to the ratio of the third to the fourth.
Page 27 - If the product of two quantities is equal to the product of two others, the...
Page 12 - In an isosceles triangle the angles opposite the equal sides are equal.
Page 49 - A Circle is a plane figure bounded by a curved line every point of which is equally distant from a point within called the center.
Page 11 - If two triangles have two sides, and the included angle of the one equal to two sides and the included angle of the other, each to each, the two triangles are equal in all respects.
Page 30 - If any number of quantities are proportional, any antecedent is to its consequent as the sum of all the antecedents is to the sum of all the consequents. Let a : b = c : d = e :f Now ab = ab (1) and by Theorem I.
Page 23 - If two triangles have two sides of one respectively equal to two sides of the other, and the angles contained by those sides supplementary, the triangles are equal in area.
Page 70 - A Cylinder is a solid figure, described by the revolution of a rectangle about one of its sides, which remains fixed.