# Elements of Geometry: Containing the First Six Books of Euclid, with a Supplement on the Quadrature of the Circle and the Geometry of Solids; to which are Added, Elements of Plane and Spherical Trigonometry

Marot & Walter, 1826 - 320 „‰ «·’ðÕ«

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 «·Þ”„ 1 13 «·Þ”„ 2 23 «·Þ”„ 3 49 «·Þ”„ 4 61 «·Þ”„ 5 63 «·Þ”„ 6 102 «·Þ”„ 7 119 «·Þ”„ 8 147
 «·Þ”„ 14 173 «·Þ”„ 15 185 «·Þ”„ 16 188 «·Þ”„ 17 202 «·Þ”„ 18 208 «·Þ”„ 19 211 «·Þ”„ 20 220 «·Þ”„ 21 231

 «·Þ”„ 9 152 «·Þ”„ 10 156 «·Þ”„ 11 160 «·Þ”„ 12 161 «·Þ”„ 13 165
 «·Þ”„ 22 264 «·Þ”„ 23 272 «·Þ”„ 24 292 «·Þ”„ 25 307

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«·’ðÕ… 125 - If two triangles have one angle of the one equal to one angle of the other and the sides about these equal angles proportional, the triangles are similar.˛
«·’ðÕ… 39 - THE straight lines which join the extremities of two equal and parallel straight lines, towards the same parts, are also themselves equal and parallel. Let AB, CD be equal and parallel straight lines, and joined towards the same parts by the straight lines AC, BD ; AC, BD are also equal and parallel.˛
«·’ðÕ… 41 - Parallelograms upon the same base and between the same parallels, are equal to one another.˛
«·’ðÕ… 19 - BG; and things that are equal to the same are equal to one another; therefore the straight line AL is equal to BC. Wherefore from the given point A a straight line AL has been drawn equal to the given straight line BC.˛
«·’ðÕ… 145 - If two triangles which have two sides of the one proportional to two sides of the other, be joined at one angle, so as to have their homologous sides parallel to one another ; the remaining sides shall be in a straight line. Let ABC, DCE be two triangles which have the two sides BA, AC proportional to the two CD, DE, viz.˛
«·’ðÕ… 30 - If, from the ends of the side of a triangle, there be drawn two straight lines to a point within the triangle, these shall be less than, the other two sides of the triangle, but shall contain a greater angle.˛
«·’ðÕ… 136 - FGL, have an angle in one equal to an angle in the other, and their sides about these equal angles proportionals ; the triangle ABE is equiangular (6.˛
«·’ðÕ… 51 - If a straight line be divided into any two parts, the square of the whole line is equal to the squares of the two parts, together with twice the rectangle contained by the parts.˛
«·’ðÕ… 20 - DEF, and be equal to it ; and the other angles of the one shall coincide with the remaining angles of the other and be equal to them, viz. the angle ABC to the angle DEF, and the angle ACB to DFE.˛
«·’ðÕ… 55 - If a straight line be divided into two equal, and also into two unequal parts ; the squares on the two unequal parts are together double of the square on half the line, and of the square on the line between the points of section.˛