| George Lees - 1826 - 276 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. PROP. XIII. THEOREM. If two triangles, BAG, EOF, have two angles, BAG, ABC, and a side... | |
| Robert Simson - Trigonometry - 1827 - 546 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,... | |
| John Radford Young - Euclid's Elements - 1827 - 228 pages
...the single interior opposite angle CDE. PROPOSITION XVir. THEOREM. In any polygon the sum of all the angles is equal to twice as many right angles as the figure lias sides, all but four right angles. For if from the vertices of the several angles, lines be drawn... | |
| Euclid, Dionysius Lardner - Euclid's Elements - 1828 - 542 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 - Geometry - 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 - 210 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,... | |
| Francis Joseph Grund - Geometry, Plane - 1830 - 274 pages
...as many times two right angles in all the angles of your figure, as there are triangles ; that is, twice as many right angles, as the figure has sides less two. SECTION II. PART II. OF GEOMETRICAL PROPORTIONS,* AND SIMILARITY OF TRIANGLES. WHENEVER we compare... | |
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