| Euclid, Dionysius Lardner - Euclid's Elements - 1828 - 544 pages
...angles. Hence it follows, that the sum of all the angles internal and external, including the reentrant **angles, is equal to twice as many right angles as the figure has sides,** together with the excess of every reentrant angle above two right angles. But (134) the sum of the... | |
| Ferdinand Rudolph Hassler - Electronic book - 1828 - 180 pages
...two right angles. § 28. THEOREM. In any rectilineal figure the sum of all the inner angles together **is equal to twice as many right angles as the figure has sides,** wanting four right angles. APPLIC. In the rectilineal figure ABDEFG, (fig. 34,) the sum of all the... | |
| Thomas Curtis - Aeronautics - 1829 - 814 pages
...118 119 липу right angles as the figure has sides. Hence the interior angles of the figure are **equal to twice as many right angles as the figure has sides** wanting four right angles. Cor. 1. All the interior angles of a quadrilateral figure are together equal... | |
| John Playfair - Geometry - 1829 - 186 pages
...diagonals &c. QED PROPOSITION L. THEOREM. All the interior angles of any rectilineal figure arc together **equal to twice as many right angles as the figure has sides,** wanting four right angles'. Let ABCDE be any rectilineal figure; all its interior angles A, B, C, D,... | |
| Pierce Morton - Geometry - 1830 - 584 pages
...producing its sides) are together equal to four right angles ; and the sum of its interior angles, together **with four right angles, is equal to twice as many right angles as the figure has sides** . . • 15 (¿•) The area of a rectilineal figure may be obtained by dividing it into triangles,... | |
| John Radford Young - Geometry, Modern - 1833 - 238 pages
...single interior opposite angle CDE. A — PROPOSITION XVII. THEOREM. In any polygon the sum of all the **angles is equal to twice as many right angles as the figure has sides,** all brtfour right angles. For if from the vertices of the several angles, lines be drawn to any point... | |
| Euclid - Euclid's Elements - 1833 - 183 pages
...the angle EDN ; therefore the reentrant angle, with the sum of all the other internal and external **angles, is equal to twice as many right angles as the figure has sides,** and to its excess EDN above two right angles : but the internal angles, with four right angles, are... | |
| Thomas Perronet Thompson - Euclid's Elements - 1833 - 150 pages
...severally capable of being so divided. And because the interior angles of each of such smaller figures are **equal to twice as many right angles as the figure has sides,** diminished by four right angles, (or, which is the same thing, to twice as many right angles as the... | |
| Charles Bonnycastle - Geometry - 1834 - 670 pages
...expressed as the following proposition : "The interior angles of any closed plane figure are together **equal to twice as many right angles as the figure has sides,** minus four right angles." 206. And as a second application of the principle in question, or, which... | |
| Mathematics - 1835
...producing its sides) are together equal to four right angles ; and the sum of its interior angles, together **with four right angles, is equal to twice as many right angles as the figure has sides** . . . 15 (c) The area of a rectilineal figure may be obtained by dividing it into triangles, having... | |
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