 | Paul Carus - 1889 - 286 pages
...adds to the stock of our knowledge something new, -.vhich we have not known before. In proving that the exterior angle of a triangle is equal to the sum of the two opposite interior angles of the same, we amplify our knowledge of the triangle by mere ratiocination,... | |
 | Edward Albert Bowser - 1890 - 420 pages
...ZABC+ZC+ZA = 2rt. Zs. (Ax. 1) QED 98. COR. 1. Since Z EBD = ZA, and Z ORE = ZC, . -.ZCBD =ZA + ZC. Hence, the exterior angle of a triangle is equal to the sum of the two opposite interior angles. 99. COR. 2. If two angles of a triangle, are given, or merely their... | |
 | William Kingdon Clifford - 1891 - 312 pages
...Fio. 21. The other form into which our proposition may be thrown is that either of the exterior angles of a triangle is equal to the sum of the two interior angles opposite to it. For, in the figure, the exterior angle A c D, together with A c B, makes two... | |
 | Henry Martyn Taylor - 1893 - 486 pages
...Construct a right-angled triangle, having given one side and the angle opposite. PROPOSITION 32. An exterior angle of a triangle is equal to the sum of the two interior opposite angles; and the sum of the three interior angles of a triangle is equal to two right angles. Let ABC be a triangle... | |
 | Henry Martyn Taylor - 1895 - 708 pages
...Construct a right-angled triangle, having given one side and the angle opposite. PROPOSITION 32. An exterior angle of a triangle is equal to the sum of the two interior opposite angles ; and the sum of the three interior angles of a triangle is equal to two right angles. Let ABC be a... | |
 | Joe Garner Estill - 1896 - 186 pages
...: AP. PB=AiPi. PiBi. Brown University, June, 1896. 1. Have you been over all the required work ? 2. The exterior angle of a triangle is equal to the sum of the opposite interior angles. 3. Find a point equidistant from two given points P and Q, and at a given... | |
 | Joe Garner Estill - 1896 - 168 pages
...prove: AP. PB=A, PL P!Bi. Brown University, June, 1896. 1. Have you been over all the required work ? 2. The exterior angle of a triangle is equal to the sum of the opposite ulterior angles. 3. Find a point equidistant from two given points P and Q, and at a given... | |
 | George Albert Wentworth - 1896 - 68 pages
...equiangular triangle, each angle is one-third of two right angles, or two-thirds of one right angle. 145. The exterior angle of a triangle is equal to the sum of the two opposite interior angles. 146. Cor. The exterior angle of a triangle is greater than either... | |
 | Andrew Wheeler Phillips, Irving Fisher - 1897 - 376 pages
...(about 600 BC). the founder of Greek mathematics and philosophy. But angle n= angle A + angle B. §58 [The exterior angle of a triangle is equal to the sum of the two opposite interior angles. Substituting A for B, n — 2A. But « is measured by arc BC. §... | |
 | Joseph Johnston Hardy - 1897 - 398 pages
...12. Two angles whose sides are perpendicular, each to each, are either equal or supplementary. 13. The exterior angle of a triangle is equal to the sum of the two opposite interior angles. 14. Two right angles are equal if the hypotenuse and an acute angle... | |
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To prove that the exterior angle of a triangle is equal to the sum of the two interior opposite angles (see fig. 
