| George Clinton Shutts - 1905 - 260 pages
...angles. Let AD represent any convex polygon. To prove that the sum of the interior angles of the polygon is equal to twice as many right angles as the polygon has sides, minus four right angles. Suggestion 1. Connect each vertex with O, any point within the polygon. 2.... | |
| Mining engineering - 1907 - 578 pages
...are there in the remaining angle? M — ///. ANS. — 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. In this case, the figure having four sides, the sum of all the interior angles... | |
| Great Britain. Board of Education - Education - 1911 - 678 pages
...angle." In the same way it was shown on the board that the sum of the interior angles of a convex polygon is equal to twice as many right angles as the polygon has sides less two. This theorem was to be repeated at the next lesson ; and the boys were asked to prove as... | |
| International Correspondence Schools - Coal mines and mining - 1913 - 360 pages
...of the exterior angles will equal four right angles. 18. The sum of the interior angles of a polygon is equal to twice as many right angles as the polygon has sides, less four right angles. For example, the sum of the interior angles of a quadrilateral is (2X4)—... | |
| Thomas J. Foster - Coal mines and mining - 1916 - 1230 pages
...the exterior angles thus formed is equal to 360°. 24. The sum of the interior angles of a polygon is equal to twice as many right angles as the polygon has sides, less four right angles. For example, the sum of the interior angles of a pentagon is (2X5)— 4 = 6... | |
| Jacob William Albert Young, Lambert Lincoln Jackson - Geometry, Plane - 1916 - 328 pages
...equilateral and equiangular. PROPOSITION XXX. THEOREM 173. The sum of the interior angles of a polygon is equal to twice as many right angles as the polygon has sides, less four right angles. Given. A polygon having n sides. To prove that the sum of the angles is 2 n... | |
| Eugenio Rignano - Reasoning - 1923 - 416 pages
...accomplished at first. "So that the angles of the polygon, if added to the angles at the vertex, are equal to twice as many right angles as the polygon has sides." Here we mentally perform the experiment which consists in substituting, in a given sum of a certain... | |
| Arthur Warry Siddons, Reginald Thomas Hughes - Geometry - 1926 - 202 pages
...Th. 1, Cor. QED 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. [For the interior and exterior angles at n vertices = nx 2 rt. L a, .'. the interior angles = (In -... | |
| Hippolyte Taine - Psychology - 1998 - 596 pages
...the polygon ; so that the angles of the polygon, if we add to them the angles at the vertices, are equal to twice as many right angles as the polygon has sides. Now we know independently that the angles at the vertices are together equal to four right angles ;... | |
| 352 pages
...right angles 266 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 266 CONGRUENT TRIANGLES. THEOREM 10. If two triangles have two sides of the one equal to two sides... | |
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