 | Charles Bonnycastle - Geometry - 1834 - 631 pages
...expressed as the following proposition : "The interior angles of any closed plane figure are together equal to twice as many right angles as the figure has sides, minus four right angles." 206. And as a second application of the principle in question, or, which... | |
 | Euclid - 1835 - 513 pages
...CBA, BAC, ACB are equal to two right angles. Wherefore, " if a side of a triangle," &c. QED COR. 1. All the interior angles of any rectilineal figure,...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... | |
 | Mathematics - 1835
...angle, is equal to two right angles (2.) ; all the interior angles, together with all the exterior angles, are equal to twice as many right angles as the figure has angles. But all the exterior angles are, by the former part of the proposition, equal to four right... | |
 | John Playfair - Euclid's Elements - 1835 - 316 pages
...by -f of one right angle. PROP. XXVI. THEOR. All the interior angles of any rectilineal figure, art equal to twice as many right angles as the figure has sides, wanting four right angles. For any rectilineal figure ABCDE can be divided into as many triangles as... | |
 | John Playfair - Geometry - 1836 - 114 pages
...three interior angles of every triangle are equal to two right angles. Which was to be proved. COR. I. All the interior angles of any rectilineal figure,...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... | |
 | Mathematics - 1836 - 472 pages
...triangle are equal to two right angles. Сон. 1. All the interior angles of any rectilineal figure are equal to twice as many right angles as the figure has sides, wanting four right anglesť 2. All the exterior angles of any rectilineal figure are to. gether equal... | |
 | Euclid, James Thomson - Geometry - 1837 - 390 pages
...therefore also the angles CBA, BAC, ACB are equal to two right angles. Wherefore, if a side, &c. Cor. 1. All the interior angles of any rectilineal figure,...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... | |
 | Andrew Bell - Euclid's Elements - 1837 - 240 pages
...angles (1. 13) ; therefore also the angles CBA, BAC, ACB, are equal to two right angles. COR. 1. — All the interior angles of any rectilineal figure,...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 - 215 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... | |
 | Adrien Marie Legendre - Geometry - 1837 - 329 pages
...two right angles, taken as many times, less two, as the polygon has sides (Prop. XXVI.) ; that is, equal to twice as many right angles as the figure has sides, wanting four right angles. Hence, the interior angles plus four right angles, is equal to twice as... | |
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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. 
