| 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...rectilineal figure are together equal to four right angles. Because every interior angle ABC, with its adjacent exte' is. i. rior ABD, is equal b to two right... | |
| Euclides - 1816 - 588 pages
...angles. Wherefore if a side of a triangle, &c. QED COR. 1. All the interior angles of any rectilineal figure, together with four right angles, are equal...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 Playfair - 1819 - 354 pages
...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 right angles. Because every interior angle ABC, with its adjacent exterior ABD, is equal (13. 1.) to two right angles... | |
| John Playfair - Circle-squaring - 1819 - 350 pages
...angles as there are triangles (32. 1.) ; that is, as there are sides in the figure BCDEF ; and because all the angles of the figure, together with four right angles, are likewise equal to twice as many right angles as there are sides in the figure (cor. 1. 32. 1.) ; therefore... | |
| Euclid, Robert Simson - Geometry - 1821 - 514 pages
...angles. Wherefore if a side of a triangle, &c. QED COK. 1. All the interior aigles of any rectilineal figure, together with four right angles, are equal to twice as many right E' angles as the figure has sides. For any rectilineal figure ABCDE can be divided into as many triangles... | |
| Euclid - 1822 - 222 pages
...therefore equal to B AE and EAC. Cor. 6. All the internal angles of any rectilineal figure, ABCDE, together with four right angles, are equal to twice as many right angles as the figure has sides. Take any point F within the figure and draw the right lines FA, FB, FC, FD, and FE. There are formed... | |
| Rev. John Allen - Astronomy - 1822 - 508 pages
...as many right angles, except four, as the figure has sides ; and all tbe angles of these triangles are equal to twice as many right angles as the figure has sides (32. 1 /CM.), therefore the angles of these triangles which are at their common vertex A, being those... | |
| Rev. John Allen - Astronomy - 1822 - 516 pages
...two right angles [13. 1} ; therefore all the exterior and interior angles of the figure are together equal to twice as many right angles as the figure has sides ; but the interior angles are equal to twice as many right angles, except four, as the figure has sides... | |
| Charles Hutton - Mathematics - 1822 - 616 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 of the angles of the triangles,... | |
| |