| Euclides - 1845 - 546 pages
...any two of its opposite angles shall together be equal to two right angles. Join AC, BD. And because the three angles of every triangle are equal to two right angles, (i. 32.) the three angles of the triangle CAB, viz. the angles CAB, ABC, BCA, are equal to two right... | |
| Edward Shaw - Masonry - 1846 - 342 pages
...straight lines AF and BD, and consequently making the angle at G equal to the angle F А С ; and since the three angles of every triangle are equal to two right angles, and since the angles FA С, С AB, BAE, are also equal to two right angles, and since F А С is equal... | |
| Euclid, John Playfair - Euclid's Elements - 1846 - 334 pages
...triangles, the four oblique angles of which are equal to the three angles of the triangle, therefore the three angles of every triangle are equal to two right angles. ing the Elements. It proceeds, like that of the French Geometer, by demonstrating, in the first place,... | |
| Charles William Hackley - Geometry - 1847 - 248 pages
...A, O ; B, O ; C, O ; D, O ; E, O. Then, since the sum of all the angles of every triangle is always equal to two right angles, the sum of all the angles of the triangles APB, BPC, ..... about the point P, will be equal to the sum of all the angles of the equal... | |
| David Benedict - Baptists - 1848 - 1024 pages
...not a head for the philosophy of language; and 1 say this with as liltle bad leeling as I say that the three angles of every triangle are equal to two right angles. " That Mr. President Beecher will be immersed in. one of the great American rivers, is now very improbable... | |
| Elias Loomis - Conic sections - 1849 - 252 pages
...part of four right angles (Prop. II., Sch. 1), or the third part of two right angles. Also, because the three angles of every triangle are equal to two right angles, the two angles OAB, OBA are together equal to two thirds of two jj^—^C right angles; and since AO is... | |
| Edward Beecher - Baptism - 1849 - 368 pages
...not a head for the philosophy of language : and I say this with as little bad feeling as I say that the three angles of every triangle are equal to two right angles." This is certainly an illustrious specimen of genuine Attic Salt. Dr. Carson, no doubt, has monopolized... | |
| Thomas Brown, James Parkinson Boyle - Philosophy - 1849 - 370 pages
...If then we can only enunciate, but not conceive, a general proposition, we can never be certain that the three angles of every triangle are equal to two right angles, until it has been demonstrated of triangles of every variety of figure ; and before this can be done,... | |
| John Mitchell Mason - Presbyterian Church - 1849 - 604 pages
...certainty. In mathematical reasoning, our knowledge is greater than our ignorance. When you have proved that the three angles of every triangle are equal to two right angles, there is an end of doubt; because there are no materials for ignorance to work up into phantoms ; but... | |
| John F. Heather - Scientific apparatus and instruments - 1849 - 208 pages
...two angles H i A and '-A HA i ; and because the vertical angles A v H and iv E are equal, and that the three angles of every triangle are equal to two right angles, therefore the two angles VIE and s EH are, together, equal to the two angles AH v and HA i, and therefore... | |
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