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Sides 5 6 7 8 9 10 To find the area of a polygon: Multiply the sum of the sides (perimeter of the polygon) by the perpendicular dropped from its center to one of its sides, and half the product will be the area. This rule applies to all regular polygons....

The Builder's Practical Guide: Containing a Complete Explanation of the ... - Page 681
by John Nicholson (Civil engineer) - 1830 - 182 pages
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The Advanced Machinist: A Practical and Educational Treatise, with Illustrations

Nehemiah Hawkins - Machine-shop practice - 1903 - 362 pages

...the sum of the sides, or perimeter of the polygon, by the perpendicular dropped from its center to one of its sides, and half the product will be the area. This rule applies to all regular polygons. Fig. 12. EXAMPLE. — What is the area of a regular pentagon,...

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