| Robert Simson - Trigonometry - 1827 - 513 pages
...zi. 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... | |
| John Radford Young - Euclid's Elements - 1827 - 246 pages
...in each triangle amounts to two right angles, therefore the angles of all the triangles are together **equal to twice as many right angles as the figure has sides,** that is to say, the sum of the angles of the polygon, together with those about the point within it,... | |
| Euclid, Dionysius Lardner - Euclid's Elements - 1828 - 544 pages
...excess of every reentrant angle above two right angles. But (134) the sum of the internal angles alone **is equal to twice as many right angles as the figure has sides,** deducting four ; hence the sum of the external angles must be equal to those four right angles, together... | |
| 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... | |
| 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,... | |
| 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... | |
| Pierce Morton - Geometry - 1830 - 584 pages
...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,... | |
| Euclid - Euclid's Elements - 1833 - 183 pages
...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... | |
| John Radford Young - Geometry, Modern - 1833 - 240 pages
...interior opposite angle CDE. A•B 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 but four right angles. For if from the vertices of the several angles, lines be drawn to any point... | |
| 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... | |
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