1.Find the value of n if the sum of interior angles of an n-sides polygon
is 156°*n
2.if the exterior angles of a heptagon are 30°,40°,50°,60°,2x,1/3x+30°and 1/5x+36°,find x
中二數學！！！！！
2008-01-25 7:35 pm
回答 (3)
2008-01-25 9:02 pm
✔ 最佳答案
1.(n-2)*180/n = 156
180n - 360 = 156n
24n = 360
n = 15
2.
30 + 40 + 50 + 60 + 2x + x/3 + 30 + x/5 + 36 + ( 7 - 2 ) * 180 = 7 * 180
1146 + 38x/15 = 1260
38x/15 = 114
x/15 = 3
x = 45
參考: 自己
2008-01-27 1:52 am
好好！
2008-01-26 12:28 am
(1)
(n-2)*180/n = 156
180n - 360 = 156n
24n = 360
n = 15
(2)
30 + 40 + 50 + 60 + 2x + x/3 + 30 + x/5 + 36 + ( 7 - 2 ) * 180 = 7 * 180
1146 + 38x/15 = 1260
38x/15 = 114
x/15 = 3
x = 45
Do you unstand ?
(n-2)*180/n = 156
180n - 360 = 156n
24n = 360
n = 15
(2)
30 + 40 + 50 + 60 + 2x + x/3 + 30 + x/5 + 36 + ( 7 - 2 ) * 180 = 7 * 180
1146 + 38x/15 = 1260
38x/15 = 114
x/15 = 3
x = 45
Do you unstand ?
收錄日期: 2021-04-23 22:41:32
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https://hk.answers.yahoo.com/question/index?qid=20080125000051KK00702