In each of the following figures,each marked angle is an interior angle or an exterior angle of the polygon.Find x.
http://i137.photobucket.com/albums/q209/ling8383/7a.jpg
問1題數學題~(最佳回答有10分)
2007-03-19 2:49 am
回答 (2)
2007-03-19 4:36 am
✔ 最佳答案
expend PE to G(當有)∠PAB =180°-50°(adj. ∠s on st. line)
∠DEG=180°-7x (adj. ∠s on st. line)
180°-50°+180°-7x+30°+6x+2x=360°(sum of ext. ∠s of polygon)
x+340°=360°
x=20°
2007-03-19 2:59 am
180 - 50 + 180 - 7x + 30 + 6x + 2x = 360
x + 340 = 360
x = 20
x + 340 = 360
x = 20
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https://hk.answers.yahoo.com/question/index?qid=20070318000051KK04190