 | Florian Cajori - 1893 - 478 σελίδες
...axioms, and, in short, came to make perfect demonstrations. In this way he arrived unaided at the theorem that the sum of the three angles of a triangle is equal to two right angles. His father caught him in the act of studying this theorem, and was so astonished at the sublimity... | |
 | William C. Bartol - 1893 - 106 σελίδες
...lines cannot meet. 353. Any side of a triangle is less than the sum of the other two sides. 354. The sum of the three angles of a triangle is equal to two right angles. 355. Two triangles are equal in all respects when two sides and the included angle of the one... | |
 | John Tilden Prince - 1894 - 254 σελίδες
...point is equal to 360°. 6. The opposite angles made by two lines crossing each other are equal. 7. The sum of the three angles of a triangle is equal to two right angles. The sum of the angles of a polygon is equal to two right angles taken as many times as the... | |
 | 1878 - 804 σελίδες
...certain inferences. Locke explains it as follows: After remarking that the mathematician positively knows that the sum of the three angles of a triangle is equal to two right angles because he apprehends the geometrical proof, he thus continues : " But another man who never... | |
 | Edwin Pliny Seaver, George Augustus Walton - 1895 - 412 σελίδες
...and cut it out. Tear off C FIG. 24. two of the angles and place them, as in Fig. 24, so as to show that The sum of the three angles of a triangle is equal to two right angles. e. How many degrees are there in each angle of an equilateral triangle ? /. If the two acute... | |
 | William Jay Youmans - 1897 - 902 σελίδες
...invention, and judgment" Instead of a series of written proofs to memorize, such as, for instance, the sum of the three angles of a triangle is equal to two right angles, the student takes the triangle, and, with suggestions from the teacher where necessary, works... | |
 | Joe Garner Estill - 1896 - 186 σελίδες
...s= — g (Use logarithms.) Princeton, June, 1894. What text-book have you read ? a + b + v 1. Prove that the sum of the three angles of a triangle is equal to two right angles. Define triangle, right angle, right triangle, scalene triangle. 3. Prove that an angle inscribed... | |
 | Joe Garner Estill - 1896 - 168 σελίδες
...numerical value. Princeton, June, 1896. State what text-book you have read and how much of it. 1. Prove that the sum of the three angles of a triangle is equal to two right angles ; and that the sum of all the interior angles of a polygon of n sides is equal to (n — 2)... | |
 | Ephraim Hunt - 1896 - 120 σελίδες
...three angles of any triangle ? LESSON XXV. Review Lesson XIV. Draw any scalene triangle. PROBLEM. The sum of the three angles of a triangle is equal to two right angles. Solution. Letter the triangle, and produce the base to D. (1) The exterior angle and its adjacent... | |
 | Joe Garner Estill - 1896 - 214 σελίδες
...diameter and weighing 8.2 ounces per square foot. Yale, June, 1896. GEOMETRY (A). TIMB, ONE HOUR. 1. The sum of the three angles of a triangle is equal to two right angles. 2. Construct a circle having its centre in a given line and passing through two given points.... | |
| |
Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 
