| Euclides - 1838 - 264 pages
...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.... | |
| Dionysius Lardner - Curves, Plane - 1840 - 386 pages
...external angles ; for, the sum of all the angles internal and external including the convex angles, **is equal to twice as many right angles as the figure has sides,** together with the excess of every convex angle above two right angles. But the sum of the internal... | |
| Euclides - 1840 - 194 pages
...right angles. Therefore, all the external, with all the internal angles of the figure, are together **equal to twice as many right angles as the figure has sides** ; that is to say, according to the preceding corollary, they are equal to all the internal angles of... | |
| Adrien Marie Legendre - Geometry - 1841 - 288 pages
...C ; for, by adding to each the angle ABC, the sums are each equal to two right angles. THEOREM. 64. **The sum of all the interior angles of a polygon is equal to** as many times two right angles as there are units in the number of sides minus two. Fig. 42. Demonstration.... | |
| Euclides - Geometry - 1841 - 378 pages
...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... | |
| Charles Waterhouse - Arithmetic - 1842 - 180 pages
...sum of the three angles is equal to two right angles ; in a square, there are four right angles, 5. **The sum of all the interior angles of a polygon, is equal to** as many times two right angles as there are units in the number of sides less two. NOTE. — A re-entering... | |
| John Playfair - Euclid's Elements - 1842 - 332 pages
...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... | |
| Euclides - 1842 - 320 pages
...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.... | |
| Charles WATERHOUSE - Arithmetic - 1844 - 228 pages
...two right angles. -3. In an isosceles triangle, the angles opposite to the equal sides are equal. 4. **The sum of all the interior angles of a polygon, is equal to** as many two right angles, as there are units in the number of sides, less two. 5. Of two sides of a... | |
| Nicholas Tillinghast - Geometry, Plane - 1844 - 110 pages
...be 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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