| Thomas Franklin Holgate - Geometry - 1901 - 460 pages
...third side has also the greater included angle. § 80. 9. THEOREMS ON THE PROPERTIES OF TRIANGLES. (1) **In an isosceles triangle, the angles opposite the equal sides are equal.** § 48. (2) The straight line which bisects the vertical angle of an isosceles triangle also bisects... | |
| George Albert Wentworth - Geometry, Solid - 1902 - 248 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... | |
| Alan Sanders - Geometry - 1903 - 392 pages
...of the other pair of vertical angles. Find the values of the four angles. PROPOSITION X. THEOREM 81. **In an isosceles triangle, the angles opposite the equal sides are equal. Let** ABC be an isosceles A, having AB = BC. To Prove ZA = /L C. Proof. Draw BD bisecting AC. (§ 55.) B... | |
| Fletcher Durell - Geometry - 1911 - 553 pages
...=& DEF, Art. 47. (geometric figures which coincide are equal), Qc 1. B. PROPOSITION IX. THEOREM 99. **In an isosceles triangle the angles opposite the equal sides are equal,** B Given the isosceles A ABC in which AB = BC. To prove ZA - Z C. Proof e Let BD be drawn so as to bisect... | |
| Fletcher Durell - Geometry, Solid - 1904 - 232 pages
...hypotenuse and an acute angle of one are equal to the hypotenuse and. an acute angle of the other. 99. **In an isosceles triangle the angles opposite the equal sides are equal.** 100. // two angles of a triangle are equal, the sides opposite are equal, and the triangle is isosceles.... | |
| Fletcher Durell - Geometry, Plane - 1904 - 382 pages
...ABC= A DEF, (geometric figures which coincide are equal) . Art. 47. Q, ED 'PROPOSITION IX. THEOREM 99. **In an isosceles triangle the angles opposite the equal sides are equal.** B Given the isosceles A ABC in which AB=BC. To prove ZA = /. C. Proof. Let BD be drawn so as to bisect... | |
| George Albert Wentworth - Geometry - 1904 - 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.** B Z> C Let ABC be an isosceles triangle, having AB and AC equal. To prove that ZB = Z C. Proof. Suppose... | |
| William Chauvenet - 1905 - 336 pages
...the one are respectively equal to a side and the two adjacent angles of the other. PROPOSITION VIII. **In an isosceles triangle the angles opposite the equal sides are equal.** Corollary. The straight line bisecting the vertical angle of an isosceles triangle bisects the base,... | |
| Cora Lenore Williams - Geometry - 1905 - 122 pages
...of a triangle to the middle point of the opposite side is called the median to that side. Prop. 3. **In an isosceles triangle, the angles opposite the equal sides are equal.** Prop. 4. An equilateral triangle is also equiangular. Prop. 5. If two angles of a triangle are equal,... | |
| International Correspondence Schools - Building - 1906 - 620 pages
...equal to the angle C" AD, or to C' A1 B1, and by Art. 74 the triangles CA B and C' A' B' are equal. 76. **In an isosceles triangle, the angles opposite the equal sides are equal. Let** ABC, Fig. 51, be an isosceles triangle in which AB -B C. Draw the bisector BD of the angle B. Then,... | |
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