| Andrew Bell, Robert Simson - Euclid's Elements - 1837 - 290 pages
...angles. 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** be divided into as many triangles as the figure has sides, by drawing straight lines from a point F... | |
| Charles Reiner - Geometry - 1837 - 254 pages
...vertex of these triangles = 4 rt. /.s; therefore, the sum 01 the interior angles of any polygon is **equal to twice as many right angles as the figure has sides** less [minus] four. M.—If the number of sides be three, four, five, six, seven, &c., what is the sum... | |
| Euclides - 1838 - 264 pages
...together with four right angles. Therefore all the angles of the figure, together with four right angles, **are equal to twice as many right angles as the figure has sides.** COB. 2. — All the exterior angles of any rectilineal figure are together equal to four right angles.... | |
| Euclides - 1840 - 192 pages
...two right angles. All the angles, therefore, of the triangles into which the AE figure is divided, **are equal to twice as many right angles as the figure has sides.** But of these, the angles round the point F are equal to four right angles (Prop. 13, cor.) : if these... | |
| Dionysius Lardner - Curves, Plane - 1840 - 386 pages
...supplement of its adjacent external angle, the internal and external angles, taken together, will be **equal to twice as many right angles as the figure has sides** ; but, from what has been already shown, the external angles alone are equal to four right angles.... | |
| Euclides - Geometry - 1841 - 378 pages
...&c. QED 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 Playfair - Euclid's Elements - 1842 - 332 pages
...as 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... | |
| Euclides - 1842 - 316 pages
...together with four right angles. Therefore all the angles of the figure, 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.... | |
| John Playfair - Euclid's Elements - 1844 - 338 pages
...many right angles as the figure has sides, wanting four. For all the angles exterior and interior arc **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... | |
| Nicholas Tillinghast - Geometry, Plane - 1844 - 110 pages
...two regular polygons, having the same number of sides. The sum of all the angles in each figure is **equal to twice as many right angles as the figure has sides,** less four right angles (BI A{ Prop. 13), and as the number of sides is the same in each figure, the... | |
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