 | William James Milne - Geometry - 1899 - 398 pages
...of sides. To prove ABCDE and FGHJK similar. Proof. By § 166, the sum of the angles of each polygon is equal to twice as many right angles as the polygon has sides less two. Since, § 374, each polygon is equiangular, and since each contains the same number of angles... | |
 | William James Milne - Geometry - 1899 - 404 pages
...polygon of any number (n) of sides, as ABCDE. Ef To prove the sum of the angles, A, B, C, D, and E equal to twice as many right angles as the polygon has sides less two. Proof. From any vertex, as J,draw the diagonals, JCand AD. The number of triangles thus formed... | |
 | International Correspondence Schools - Mining engineering - 1900 - 728 pages
...regular polygon. If not, it is an irregular polygon. The sum of the interior angles of any polygon is equal to twice as many right angles as the polygon has sides, less four right angles. To Find the Area of Any Regular Polygon.— Square one of its sides and multiply... | |
 | Science - 1900 - 872 pages
...necessary to apply the well-known principle of geometry that the turn of UK interior angle* n_f a polygon is equal to twice as many right angles as the polygon has sides, less four right angle*. Thia applies to figures having any number of sides, without regard to whether... | |
 | Edward Brooks - Geometry, Modern - 1901 - 278 pages
...etc. Proof.— First, the poly- B_ gons are mutually equiangular. For every angle in either polygon is equal to twice as many right angles as the polygon has sides, less four right angles,, divided by the number of sides. I. 36, 2. And since the number of sides in... | |
 | Charles Godfrey, Arthur Warry Siddons - Geometry - 1903 - 384 pages
...of L. s at O = 4 rt. L s. I. 1 Cor. q. ED COR. The sum of the interior angles of any convex polygon together with four right angles is equal to twice as many right angles as the polygon has sides. Ex. 388. Three of the exterior angles of a quadrilateral are 79°, 117°, 65° ; find the other exterior... | |
 | John Alton Avery - Geometry, Modern - 1903 - 136 pages
...of a parallelogram bisect each other. 99. Theorem XLIV. The sum of the interior angles of a polygon is equal to twice as many right angles as the polygon has sides, minus four right angles. 100. Corollary. In an equiangular polygon of n sides, the value , . , . (2n... | |
 | American School (Chicago, Ill.) - Engineering - 1903 - 390 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. RATIO AND PROPORTION. DEFINITIONS. (NOTE. It is necessary to understand the elementary principles... | |
 | Education - 1904 - 938 pages
...alternate Interior angles are equal. 5. Demonstrate: The sum of the interior angles of any convex polygon is equal to twice as many right angles as the polygon has sides, minus four right angles. 6. Show that the area of a square inscribed in a circle is equal to ane-half... | |
 | Reginald Empson Middleton - Surveying - 1904 - 332 pages
...close polygon, which may be summarised as follows. The sum of the ' interior ' angles augmented by four right angles is equal to twice as many right angles as the figure has sides. The sum of the ' exterior ' angles diminished by four right angles is equal to twice... | |
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Hence, the interior angles plus four right angles, is equal to twice as many right angles as the polygon has sides, and consequently, equal to the sum of the interior angles plus the exterior angles. 
