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條問題係:
In △ABC as shown,AD is the angle bisector of ∠BAC,∠B=65° and
∠C=45°.Find
(a) ∠ADB
(b) ∠ADC
F.2 plane geometry
2008-04-27 7:10 pm
回答 (1)
2008-04-27 7:36 pm
✔ 最佳答案
(a)∠BAD = ∠CAD (given)
∠BAC= 180°- 65°-45° (∠ sum of △)
2∠BAD = 70°
∠BAD= 35°
∠ADB = 180°-65°-∠BAD (∠ sum of △)
∠ADB= 80°
(b)
∠ADC = 65°+∠BAD (ext. ∠of △)
∠ADC = 65° +35°
∠ADC = 100°
收錄日期: 2021-04-23 20:40:14
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080427000051KK00859