| Canadian Mining Institute - Mineral industries - 1912 - 778 pages
...know from Euclid that the sum of the interior angles of any closed figure bounded by straight lines **is equal to twice as many right angles as the figure has sides** less four right angles; figure A has 12 sides, therefore, the interior angles are equal to 20 right... | |
| Hippolyte Taine - Psychology - 1998 - 596 pages
...to the 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 which are connected.... | |
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