 | Robert Louis Short, William Harris Elson - Mathematics - 1910 - 202 pages
...isosceles triangle has two sides equal. An equilateral triangle has three sides equal. THEOREM III 78. In an isosceles triangle the angles opposite the equal sides are equal. Draw line AB. With A and B as centers and the same radius greater than 1 AB, describe arcs intersecting... | |
 | George William Myers - Mathematics - 1910 - 304 pages
...If the sum of two adjacent angles is a straight angle, their exterior sides form a straight line. 6. In an isosceles triangle the angles opposite the equal sides are equal. 7. If two angles of a triangle are equal, the sides opposite them are equal. 8. The sum of the acute... | |
 | David Eugene Smith - Geometry - 1911 - 360 pages
...there. There are other dual features that are seen in geometry liesides those given above. THEOREM. In an isosceles triangle the angles opposite the equal sides are equal. This is Euclid's Proposition 5, the second of his theorems, but he adds, "and if the equal straight... | |
 | Geometry, Plane - 1911 - 192 pages
...examination book the name of the text-book he has used. Omit two of the starred questions. * 1. Prove that in an isosceles triangle the angles opposite the equal sides are equal. Given two lines AB and BC. Show how to draw through a point D of AB a third line making with BC the... | |
 | William Betz, Harrison Emmett Webb - Geometry, Modern - 1912 - 368 pages
...? 5. ...ZB = ZC. Ax. 1 (Each being equal to ZW.) REMARK. Proposition III may also be stated thus : In an isosceles triangle the angles opposite the equal sides are equal. 139. COROLLARY.* An equilateral triangle is also equiangular. For any side may be regarded as the base... | |
 | George Albert Wentworth, David Eugene Smith - Geometry - 1913 - 496 pages
...C, on this 7y perpendicular, and in line with 0 and P. They then found PROPOSITION IV. THEOREM 74. In an isosceles triangle the angles opposite the equal sides are equal. Given the isosceles triangle ABC, with AC equal to BC. To prove that ZA = ZB Proof . Suppose CD drawn... | |
 | Walter Burton Ford, Charles Ammerman - Geometry, Plane - 1913 - 378 pages
...enabling us to give proofs in a more condensed form. See the list of symbols, p. 34. 40. Theorem III. In an isosceles triangle the angles opposite the equal sides are equal. o Fio. 32 Given the isosceles triangle ABC in which AC = BC. To prove that Z A = Z B. Proof. Draw CD... | |
 | Walter Burton Ford, Charles Ammerman - Geometry, Solid - 1913 - 176 pages
...one are equal, respectively, to'an] acute angle and its adjacent side in the other. 40. Theorem III. In an isosceles triangle the angles opposite the equal sides are equal. 41. Corollary 1. If a triangle is equilateral, it is also equiangular. 43. Theorem IV. Tfie bisector... | |
 | International Correspondence Schools - Coal mines and mining - 1913 - 360 pages
...sum of the lengths of any two sides of a triangle is greater than the length of the third side. 9. In an isosceles triangle, the angles opposite the equal sides are equal. 10. In any triangle, the sum of the three angles is equal to two right angles, or 180°. 11. If two... | |
 | Walter Burton Ford, Earle Raymond Hedrick - Geometry, Modern - 1913 - 272 pages
...enabling us to give proofs in a more condensed form. See the list of symbols, p. 34. 40. Theorem III. In an isosceles triangle the angles opposite the equal sides are equal. c D FIG. 32 B Given the isosceles triangle ABC in which AC = BO. To prove that ZA = Z B. Proof. Draw... | |
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In an isosceles triangle, the angles opposite the equal sides are equal. Let ABC be an isosceles triangle, in which the side AB is equal to the side AC ; then will the angle B be equal to the angle C. 
