 | Nathan Scholfield - 1845 - 896 pages
...BAE is equal to the angle B, and the part DAE is equal to the angle C. PROPOSITION XXVIII. THEOREM. The sum of all the interior angles of a polygon is equal to tvire as many ri^ht angles as ike figure has sides, less four right angles. Let ABCDEFG he the proposed... | |
 | Euclid, James Thomson - Geometry - 1845 - 380 pages
...&c. 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... | |
 | Euclides - 1845 - 544 pages
...angles. But all the interior angles of any rectilinear figure together with four right angles, are equal to twice as many right angles as the figure has sides, that is, if we agree to assume IT to designate two right angles, .-. nS + 27T = ntr, and «6 = »ir... | |
 | Euclid - Geometry - 1845 - 218 pages
...QED COB. 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. the angles of these triangles are equal to twice as many right angles as there are triangles, that... | |
 | Dennis M'Curdy - Geometry - 1846 - 168 pages
...p. 13. (e)p.29; Cor. 1. All the interior angles of any rectilineal figure and four right angles, are equal to twice as many right angles as the figure has sides. For, about a point within the figure, as many triangles may be formed as the figure has sides, each... | |
 | Euclides - 1846 - 292 pages
...QEU 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... | |
 | Euclides - 1846 - 272 pages
...There are as many triangles constructed as the figure has sides, and therefore all these angles will be equal to twice as many right angles as the figure has sides (by Prop. 32) ; from these take four right angles, for the angles at the point F (by Cor. 3 Prop. 13),... | |
 | Euclid, John Playfair - Euclid's Elements - 1846 - 332 pages
...many right angles as the figure has sides, wanting four. For all the angles exterior and interior are equal to twice as many right angles as the figure has sides ; but the exterior are equal to four right angles ; therefore the interior are equal to twice as many... | |
 | Anthony Nesbit - Plane trigonometry - 1847 - 492 pages
...prove the accuracy of the previous work. Moreover, since the sum of all the interior angles of any polygon is equal to twice as many right angles as the figure has sides, lessened by four ; as the given figure has five sides, the sum of all its interior angles must be 2x5... | |
 | Benjamin Peirce - Geometry - 1847 - 204 pages
...the exterior angle BCD is equal to the sum of the two opposite interior angles A and B. 72. Theorem. The sum of all the interior angles of a polygon is equal to as many times two right angles as it has sides minus two. Proof. Let ABCDE, &c. (fig. 37), be the given... | |
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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 sides. 
