 | Mathematics - 1801 - 656 pages
...;• add all the inward angles A, B, C, &c. together, and when the work is right, their sum will be equal to twice as many right angles, as the figure has sides, wanting four right angles. And when there is an angle, as F, that bends inward, and you measure the... | |
 | Robert Simson - Trigonometry - 1804 - 528 pages
...CBA, BAC, ACB are equal to two right angles. wherefore if a fide of a triangle, &c. Q^ED . CoR. i. All the interior angles of any rectilineal figure,...equal to twice as many right angles as the figure has fides. For any reCtilineal figure ABCDE can be divided into as many triangles as the figure has fides,... | |
 | John Playfair, Euclid - Circle-squaring - 1804 - 468 pages
...Wherefore^ if a fide of a triangle; &c. C^ED CoR. i. All the interior angles of any reftilmeal figure, are equal to twice as many right angles as the figure has fides, wanting four right angles. For any reftilineal figure ABCDE can be divided into as many triangles... | |
 | Robert Simson - Trigonometry - 1806 - 548 pages
...the triangles ; that is », to15. 1. gether with four right angles. Therefore all the angles of the figure, together with four right angles, are equal...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 - Mathematics - 1806 - 320 pages
...to 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... | |
 | Charles Hutton - Mathematics - 1807 - 460 pages
...work ; add all the inward angles A, B, c, &c, together ; for when the work is right, their sum will ba equal to twice as many right angles as the figure has sides, wanting 4 right angles. But when there is an angle, as F, that bends inwards, and you measure the external... | |
 | Sir John Leslie - Geometry, Analytic - 1809 - 542 pages
...interior one AED, is equal to two right angles. All the exterior angles therefore, added to the interior angles, are equal to twice as many right angles as the figure has sides. Consequently the exterior angles are equal to the four right angles which, by the last Proposition,... | |
 | Sir John Leslie - Geometry, Plane - 1809 - 522 pages
...is equal to two right angles. All the exterior angles therefore, added to the interior angles, ftre equal to twice as many right angles as the figure has sides. Consequently the exterior angles are equal to the four right angles which, by the last Proposition,... | |
 | Charles Hutton - Mathematics - 1811 - 406 pages
...triangles, is equal to two right angles (th. 17); therefore the sum of the angles of all the triangles is equal to twice as many right angles as the figure has sides. But the sum of all the angles about the point P, which are so many many of the angles of the triangles,... | |
 | Euclides - 1814 - 560 pages
...the same angles are equal to the angles of the figure, together with the angles at the point F, which 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.... | |
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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 sidef. For any rectilineal figure ABCDE can be divided into as many triangles as the figure has sides, by drawing... 
