 | Electrical engineering - 1897 - 672 pages
...to the base extended. Thus, in Figs. 33 and C 34, BD is the altitude FIG. 33. of the triangles ABC. In an isosceles triangle, the angles opposite the equal sides are equal. Thus, in Fig. 35, AB = BC; hence, angle C= angle A. In any isosceles triangle, if a perpendicular be... | |
 | International Correspondence Schools - Surveying - 1898 - 518 pages
...to the base produced. Thus, in Figs. 32 and33, CBD is the altitude of the triangles AB C. PlC. 47. In an isosceles triangle, the angles opposite the equal sides are equal. Thus, in Fig. 34, AB = BC; hence, angle C = angle A. Therefore, if two angles of any triangle are equal,... | |
 | Webster Wells - Geometry - 1898 - 284 pages
...hypothesi£ that BC is > EF. Then, if ZA can be neither equal to ZD, nor < ZD, ZA> PROP. XXX. THEOREM. 93. In an isosceles triangle, the angles opposite the equal sides are equal. D Given AC and BC the equal sides of isosceles A ABC. To Prove ZA = Z B. Proof. Draw line CD _L AB.... | |
 | James Howard Gore - Geometry - 1898 - 232 pages
...obtuse-angled triangle the sum of the acute angles is less than a right angle. PROPOSITION XVII. THEOREM. 93. In an isosceles triangle the angles opposite the equal sides are equal. Let ABC be an isosceles triangle in which AC and BC are the equal sides. To prove that Z A = Z B. Draw... | |
 | William James Milne - Geometry, Modern - 1899 - 258 pages
...opposite the «qual sides compare in size ? 2. How do the angles of an equilateral triangle .compare? Theorem. In an isosceles triangle the angles opposite the equal sides are equal. Data : Any isosceles triangle, as ABC, in which C = BC. To prove angle A = angle B. Proof. Draw CD... | |
 | International Correspondence Schools - Civil engineering - 1899 - 722 pages
...the base produced. Thus, in Figs. 32 and33, C BD is the altitude of the triangles AB C. Via. ! 47. In an isosceles triangle, the angles opposite the equal sides are equal. Thus, in Fig. 34, AB — £C; hence, angle C = angle A. Therefore, if two angles of any triangle are... | |
 | George Albert Wentworth - Geometry - 1899 - 496 pages
...always true, just as the converse of a theorem is not always true. PROPOSITION XXII. THEOREM. 145. In an isosceles triangle the angles opposite the equal sides are equal. BDC Let ABC be an isosceles triangle, having AB and AC equal. To prove that ZB = Z C. Proof. Suppose... | |
 | George Albert Wentworth - Geometry, Solid - 1899 - 246 pages
...angle of the other. 144. Two right triangles are equal if their legs are equal, each to each. 145. In an isosceles triangle the angles opposite the equal sides are equal. 147. If two angles of a triangle are equal, the sides opposite the equal angles are equal, and the... | |
 | Charles Austin Hobbs - Geometry, Plane - 1899 - 266 pages
...angles are opposite the legs. Consult Prop. 37, Cor. III. and Prop. 8. Proposition 41. Theorem. 52. In an isosceles triangle, the angles opposite the equal sides are equal. HINT. Draw a line bisecting the vertical angle. COB. An equilateral triangle is also equiangular. Proposition... | |
 | George Albert Wentworth - Geometry, Plane - 1899 - 278 pages
...the converge of a theorem is not always true. BOOK I. PLANE GEOMETRY. PROPOSITION XXII. THEOREM. 145. In an isosceles triangle the angles opposite the equal sides are equal. • B na Let ABC be an isosceles triangle, having AB and AC equal. To prove that ZB = Z C. . Proof.... | |
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Theorem. In an isosceles triangle the angles opposite the equal sides are equal. 
