| Euclid - Geometry - 1845 - 199 pages
...angles CBA, BAC, ACB, are equal to two right angles. Wherefore, if a side of a triangle, &c. QED COB. 1. **All the interior angles of any rectilineal figure,...twice as many right angles as the figure has sides.** the angles of these triangles are equal to twice as many right angles as there are triangles, that... | |
| Nathan Scholfield - 1845
...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... | |
| Euclides - 1846
...angles BAC, ACB, CBA, are equal to two right angles. Wherefore, If a side of a triangle %c. QEU COR. 1. **All the interior angles of any rectilineal figure,...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... | |
| Dennis M'Curdy - Geometry - 1846 - 138 pages
...ax. 2 ! (4) p. 27; (c) p. 13. (e)p.29; Cor. 1. All the interior angles of any rectilineal figure and **four right angles, are equal to twice as many right angles as the figure has sides.** For, about a point within the figure, as many triangles may be formed as the figure has sides, each... | |
| Euclides - 1846
...internal, are equal to twice as many right angles, as there are sides of the figure ; but the internal **with four right angles, are equal to twice as many right angles as** there are sides of the figure (by Cor. 6) ; take away from both the internal angles, and the external... | |
| John Playfair - Euclid's Elements - 1846 - 317 pages
...as the figure has sides ; but the exterior are equal to four right angles ; therefore the interior **are equal to twice as many right angles as the figure has sides,** wanting four. PROP. II. Two straight lines, which make with a third line the interior angles on the... | |
| Education - 1847
...liquidation of it. In how many years will the debt be paid off? OEOMETBY AND TRIGOSO1IETBY. SECTION I. — 1. **All the interior angles of any rectilineal figure,...twice as many right angles as the figure has sides.** 2. Equal triangles, upon equal bases in the same straight line, and towards the same parts, are between... | |
| Great Britain. Committee on Education - School buildings - 1847
...liquidation of it. In how many years will the debt be paid off? GEOMETRY AND TRIGONOMETRY. SECTION I. 1. **All the interior angles of any rectilineal figure,...equal to twice as many right angles as the figure** hag sides. 2. Equal triangles, upon equal bases in the same straight line, and towards the same parts,... | |
| Anthony Nesbit - Plane trigonometry - 1847 - 426 pages
...accuracy of the previous work. Moreover, since the sum of all the interior angles of any polygon is **equal to twice as many right angles as the figure has sides,** lessened by four ; as the given figure has five sides, the sum of all its interior angles must be 2x5... | |
| Charles William Hackley - Geometry - 1847 - 103 pages
...Hence it follows that the sum of all the inward angles of the polygon alone, A + B -f- C + D + E, is **equal to twice as many right angles as the figure has sides,** wanting the said four right angles. QED Corol. 1. In any quadrangle, the sum of all the four inward... | |
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