四/五/六/七/八邊形的內角和係度?

圖片參考：http://upload.wikimedia.org/wikipedia/commons/thumb/5/51/ExternalAngles.svg/300px-ExternalAngles.svg.png

To find the total measure of degrees in a regular polygon, (regular meaning all sides and angles are equal) you must take the number of sides the polygon has, n, subtract 2 from it, then multiply that number by 180.
Example:
A decagon, a polygon with 10 sides, is a simple shape to figure the total measure of


圖片參考：http://upload.wikimedia.org/math/9/d/9/9d943d1615847b61d371d702690649d1.png

= measure in degrees, when n = number of sides
Solution to the decagon:


圖片參考：http://upload.wikimedia.org/math/e/e/b/eebe7a5eec182e1fe9dbb21d03f8851e.png

The total measure of the decagon is 1440.
Thus,
四邊形的內角和係
(4 - 2) * 180 = 360 度
五邊形的內角和係
(5 - 2) * 180 = 540度
六邊形的內角和係
(6 - 2) * 180 = 720度
七邊形的內角和係
(7 - 2) * 180 = 900度
八邊形的內角和係
(8 - 2) * 180 = 1080度



2008-05-13 10:08:05 補充：
幫到你嗎?

四--360 五--540 六--720 七--900 八--1080

四:360
五:540
六:720
七:900
八:1080