 | Gerardus Beekman Docharty - Geometry - 1867 - 474 pages
...to twice as many right angles as the figure has sides. But the sum of all the interior angles, with four right angles, is equal to twice as many right angles as the figure has sides (th. 19) ; therefore the sum of all the interior and all the exterior angles is equal... | |
 | Eli Todd Tappan - Geometry - 1868 - 432 pages
...among the equal parts. SUM OF THE ANGLES. 433. Theorem. — The gum of all the angles of a polygon is equal to twice as many right angles as the polygon has sides, less two. For the polygon may be divided into as many triangles as it has sides, less two (417); and... | |
 | John A. Smith - 1869 - 368 pages
...well-known geometrical cannon —viz., the sum of the internal angles of any plane figure, together with four right angles, is equal to twice as many right angles as the figure has sides. angles of the triangle being known), the following computation should be made:—... | |
 | Sir Norman Lockyer - Science - 1901 - 1076 pages
...(Grynaeus-Bale, 1533 AD ) these two corollaries are given : — (1) The sum of the interior angles of any polygon is equal to twice as many right angles as the polygon has sides less two. (2) The sum of the exterior angles of any polygon is equal to four right angles. STAM. EUMORFOPOULOS.... | |
 | Elias Loomis - Geometry - 1871 - 302 pages
...ABD, is equal to two right angles (Prop. II.) ; therefore the sum of all the interior and exterior angles, is equal to twice as many right angles as the polygon has sides ; that is, they are equal to all the interior angles of the polygon, together with four right angles.... | |
 | Hippolyte Taine - Knowledge - 1871 - 606 pages
...weight of the liquid they displace. In every polygon, the sum of the internal angles together with four right angles is equal to twice as many right angles as the figure has sides. — Here are laws; each of them consists in a couple of general and abstract characters... | |
 | Henry William Watson - Geometry - 1871 - 320 pages
...bases of the triangles ABC, ACD, and so on. But the sum of all the angles of the polygon, together with four right angles, is equal to twice as many right angles as there are sides of the polygon. Also, the sum of all the angles at the bases of the triangles, together... | |
 | William Frothingham Bradbury - Geometry - 1872 - 124 pages
...the sum of the angles of all the triangles, that is, the sum of the interior angles of the polygon, is equal to twice as many right angles as the polygon has sides minus two. PRACTICAL QUESTIONS. 1. Do two lines that do not meet form an angle with each other ? Two... | |
 | Edward Olney - Geometry - 1872 - 562 pages
...one re-entrant angle. PROPOSITION XT. 253. TJieorem. — Tlie sum of the inferior angles of a polygon is equal to twice as many right angles as the polygon has sides, less four right angles. DEM. — Let n he the number of sides of any polygon ; then the sum of its... | |
 | Euclides, James Hamblin Smith - Geometry - 1872 - 376 pages
...Simson's Edition of Euclid. COR. 1. The sum of the interior angles of any rectilinear figure together with four right angles is equal to twice as many right angles as the figure has sides. jo J> Let ABCDE be any rectilinear figure. Take any pt. F within the figure, and... | |
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Hence, the interior angles plus four right angles, is equal to twice as many right angles as the polygon... 
