### тИ КщМЕ ОИ ВЯчСТЕР -сЩМТАНГ ЙЯИТИЙчР

дЕМ ЕМТОПъСАЛЕ ЙЯИТИЙщР СТИР СУМчХЕИР ТОПОХЕСъЕР.

### пЕЯИЕВЭЛЕМА

 INTRODUCTION 3 PARALLEL LINES AND SYMMETRICAL FIGURES 15 TRIANGLES 30 PARALLELOGRAMS 53 BOOK II 62 MEASUREMENT 75 PROBLEMS OF DEMONSTRATION 87 PROBLEMS OF DEMONSTRATION 129
 DIEDRAL ANGLES 207 POLYEDRAL ANGLES 215 PROBLEMS OF DEMONSTRATION 221 PYRAMIDS 243 SIMILAR POLYEDRONS 257 PROBLEMS OF CONSTRUCTION 264 THE SPHERE 272 SPHERICAL ANGLES 278

### дГЛОЖИКч АПОСПэСЛАТА

сЕКъДА 170 - The areas of two regular polygons of the same number of sides are to each other as the squares of their radii or as the squares of their apothems.
сЕКъДА 204 - If a line is perpendicular to one of two parallel lines, it is perpendicular to the other also.
сЕКъДА 106 - If a line divides two sides of a triangle proportionally, it is parallel to the third side.
сЕКъДА 5 - If the first of three quantities is greater than the second, and the second is greater than the third, then the first is greater than the third.
сЕКъДА 82 - An angle formed by a tangent and a chord is measured by one-half its intercepted arc.
сЕКъДА 73 - A line perpendicular to a radius at its extremity is tangent to the circle.
сЕКъДА 177 - C and area S. To PROVE S — ^RxC. Circumscribe a regular polygon and call its perimeter C' and area S'. Then S
сЕКъДА 285 - Two triangles are congruent if (a) two sides and the included angle of one are equal, respectively, to two sides and the included angle of the other...
сЕКъДА 45 - If, from a point within a triangle, two straight lines are drawn to the extremities of either side, their sum will be less than the sum of the other two sides of the triangle.
сЕКъДА 83 - The measure of an exterior angle of a triangle is equal to the sum of the measures of the two remote interior angles.