| Aaron Schuyler - Geometry - 1876 - 384 pages
...AD (56, 2). But B and C are opposite the equal sides, AC, AB, of the isosceles triangle ABC. Hence, in an isosceles triangle, the angles opposite the equal sides are equal. 60. Corollaries. 1. The line bisecting the vertical angle of an isosceles triangle bisects the base... | |
| George Albert Wentworth - Geometry - 1877 - 436 pages
...respectively to an homologous side and acute angle of the other. TRIANGLES. PROPOSITION XXVIII. THEOREM. 2. In an isosceles triangle the angles opposite the equal sides are equal. Let ABC be ал isosceles triangle, having tue sides AC and С B equal. ч We are to prove Z. A = ZB From... | |
| George Albert Wentworth - Geometry - 1877 - 416 pages
...respectively tcr an homologous side and acute angle of the other. TRIANGLES. PROPOSITION XXVIII. THEOREM. 112. In an isosceles triangle the angles opposite the equal sides are equal. С Let ABС be an isosceles triangle, having the sides A С and С B equal. We are to prove A = ZB... | |
| William Frothingham Bradbury - Geometry - 1880 - 260 pages
...intersection E. Therefore the two triangles coincide, and are equal in all respects. THEOREM XII. 82. In an isosceles triangle the angles opposite the equal sides are equal. In the isosceles triangle ABC let AB and BC be the equal sides ; then the angle A is equal to the angle... | |
| Cornell University - 1880 - 868 pages
...tangent to a circle, the projection of one straight line upon another, four proportional magnitudes. 2. In an isosceles triangle the angles opposite the equal sides are equal to each other. Every equilateral triangle is also equiangular. An isosceles triangle is symmetric about... | |
| Simon Newcomb - Geometry - 1881 - 418 pages
...line. 90. Def. Segments of a straight line are the parts into which it is divided. • THEOREM IX. 91. In an isosceles triangle the angles opposite the equal sides are equal to cach other. Hypothesis. ABC a triangle in which CA = CB. Conclusion. Angle A = angle B. Proof. Bisect... | |
| George Albert Wentworth - 1881 - 266 pages
...respectively to an homologous side and acute angle of the other. TRIAXGLKS. PROPOSITION XXVIII. THEOREM. 112. In an isosceles triangle the angles opposite the equal sides are equal. С Let ABC be ал isosceles triangle, having the sides AC and С B equal. We are to prove ¿ A = ¿... | |
| Franklin Ibach - Geometry - 1882 - 208 pages
...and an acute angle of the other. ВЕЪАТКШ BETWEEN THE PARTS OF A TRIANGLE. THEOREM XXXI. 94. In an isosceles triangle, the angles opposite the equal sides are equal. In the isosceles A ABC, let AC and B С be the equal sides. С ADB To prove that ¿- a = ¿- b. Let... | |
| Alfred Hix Welsh - Geometry - 1883 - 326 pages
...equal in all their parts (Th. IV)', and, consequently, the angle B is equal to the angle C. Therefore, in an isosceles triangle, the angles opposite the equal sides are equal. Cor. I.—An equilateral triangle is equiangular. For, if AB equals AC, then, by the Theorem just proved,... | |
| Edward Olney - Geometry - 1883 - 352 pages
...chords are equal, the arcs are, and hence the angles subtended by these arcs. 223. COROLLARY 3. — In an isosceles triangle the angles opposite the equal sides are equal ; and, conversely, if two angles of a triangle are equal, the sides opposite are equal, and the triangle... | |
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