teach me please!
圖片參考：http://imgcld.yimg.com/8/n/HA00407912/o/701209290032613873366520.jpg
concyclic
2012-09-29 10:33 pm
回答 (1)
2012-09-29 10:44 pm
✔ 最佳答案
因為∠BCD = ∠ABD, ∠ACD = ∠BAD (交錯弓形的圓周角)因此∠ACB
= ∠BCD + ∠ACD
= ∠ABD + ∠BAD
= 180 - ∠ADB
= 180 - 120
= 60 (A)
收錄日期: 2021-04-13 19:02:31
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120929000051KK00326