| Benjamin Peirce - Geometry - 1847 - 204 pages
...perpendicular to its base, divides it, by § 57, into the two equal triangles ABC and ABG. 65. Theorem. The sum of the three angles of any triangle is equal to two right angles. Proof. Let ABC (fig. 36) be the given triangle. Produce AC to D, and draw CE parallel to AB. The angles... | |
| Samuel Griswold Goodrich - Children's literature - 1852 - 372 pages
...be demonstrated, or something required to be done, and is accordingly either a theorem or a problem. A theorem is a demonstrative proposition, in which...when it is said that the sum of the three angles of a triangle is equal to two right angles, that is a theorem, the truth of which is demonstrated hy geometry.... | |
| Euclid, John Playfair - Geometry - 1853 - 336 pages
...or, two quantities that are each of them equal to a third quantity, are equal to each other. ftr'A Theorem is a demonstrative proposition ; in which...it is said that the sum of the three angles of any plane triangle is equal to two right angles, this is called a Theorem ; and the method of collecting... | |
| Elias Loomis - Algebra - 1855 - 356 pages
...is the statement of some property, the truth of which is required to be proved. Thus the principle that the sum of the three angles of any triangle is equal to two right angles, is a theorem, the truth of which is demonstrated by Geometry. (8.) A problem is a question requiring... | |
| John Playfair - Geometry - 1855 - 334 pages
...quantity, are equal to each other. C. A Theorem is a demonstrative proposition ; in which some property is Thus, when it is said that the sum of the three angles of any plane triangle is equal to two right angles, this is called a Theorem; and the method of collecting... | |
| Elias Loomis - Algebra - 1858 - 394 pages
...is the statement of some property, the truth of which is required to be proved. Thus the principle that the sum of the three angles of any triangle is equal to two right angles, is a theorem, the truth of which is demonstrated by Geometry. (8.) A problem is a question requiring... | |
| Charles Hutton - Mathematics - 1860 - 1014 pages
...Propotilim is something proposed to he proved, or something required to be done ; and is accordingly either a Theorem or a Problem. 6. A Theorem is a demonstrative...proved. Thus, when it is said that. The sum of the three anglas of any triangle is equal to two right angles, this is a Theorem, the truth of which is demonstrated... | |
| Horatio Nelson Robinson - Geometry - 1860 - 468 pages
...the theorem ; the sum of the angles of any parallelogram it eoual tc four right angles. THEOREM XI. The sum of the three angles of any triangle is equal to two right angles. Let AB C be a triangle, and through its vertex C / draw a line parallel to the b\e/a base AB, and produce... | |
| Elias Loomis - Algebra - 1864 - 386 pages
...is the statement of some property, the truth of which is required to be proved. Thus the principle that the sum of the three angles of any triangle is equal to two right angles, is a theorem, N the truth of which is demonstrated by Geometry. (8.) A problem is a question requiring... | |
| Horatio Nelson Robinson - Geometry - 1868 - 276 pages
...the theorem ; the sum of the angles of any parallelogram it toual k four right angles. THEOREM XI. The sum of the three angles of any triangle is equal to two right angles. Let AB O be a triangle, and through its vertex C draw a line parallel to the base AB, and produce the... | |
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