| Euclid, James Thomson - Geometry - 1837 - 410 pages
...&c. Cor. 1. All the interior angles of any rectilineal figure, together with four right angles, are equal to twice as many right angles as the figure has sides. For any rectilineal figure ABCDE can be divided into as many triangles as the figure has sides, by... | |
| Euclides - 1838 - 264 pages
...with four right angles. Therefore all the angles of the figure, together with four right angles, are equal to twice as many right angles as the figure has sides. COB. 2. — All the exterior angles of any rectilineal figure are together equal to four right angles.... | |
| Dionysius Lardner - Curves, Plane - 1840 - 386 pages
...external angles ; for, the sum of all the angles internal and external including the convex angles, is equal to twice as many right angles as the figure has sides, together with the excess of every convex angle above two right angles. But the sum of the internal... | |
| Charles Davies - Geometrical drawing - 1840 - 262 pages
...ACD, and ADE ; and the second, the similar triangles FHG, FBI, and F1K. 6. The sum of all the inward angles of any polygon is equal to twice as many right angles, wanting four, as the figure has sides. Thus, if the polygon has five sides, we have A + B + C+ D+E—W... | |
| Euclides - 1840 - 192 pages
...right angles. Therefore, all the external, with all the internal angles of the figure, are together equal to twice as many right angles as the figure has sides ; that is to say, according to the preceding corollary, they are equal to all the internal angles of... | |
| Euclides - Geometry - 1841 - 378 pages
...QED COR. 1. All the interior angles of any rectilineal figure, together with four right angles, are equal to twice as many right angles as the figure has sides. For any rectilineal figure ABCDE can be divided into as many triangles as the figure has sides, by... | |
| Euclides - 1842 - 316 pages
...with four right angles. Therefore all the angles of the figure, together with four right angles, are equal to twice as many right angles as the figure has sides. COR. 2. All the exterior angles of any rectilineal figure are together equal to four right angles.... | |
| John Playfair - Euclid's Elements - 1842 - 332 pages
...all the angles of the figure, together with four right angles, that is, the angles of the figure are equal to twice as many right angles as the figure has sides, wanting four. COR. 2. All the exterior angles of any rectilineal figure are together equal to four... | |
| Nicholas Tillinghast - Geometry, Plane - 1844 - 110 pages
...be two regular polygons, having the same number of sides. The sum of all the angles in each figure is equal to twice as many right angles as the figure has sides, less four right angles (BI A{ Prop. 13), and as the number of sides is the same in each figure, the... | |
| Nathan Scholfield - 1845 - 894 pages
...to two right angles, taken as many times, less two, as the polygon has sides (Prop. XXVIII.) ; that is, equal to twice as many right angles as the figure has sides, wanting four right angles. Hence, the interior angles plus four right angles, is equal to twice as... | |
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