In the figure (http://hk.geocities.com/ken1ken1232003/ABCDM.bmp),
AB=CDand BC=DA.
(a)Prove that angle ADB=angle CBD and angle ABD=angle CDB.
(b)Prove that AC and BD bisect each other.
註:要列式及解釋問題!
英文數學題6,急急
2006-11-17 5:08 am
回答 (1)
2006-11-17 5:26 am
✔ 最佳答案
a.AD=CB(given)AB=CD(given)
DB=BD(common side)
∴ △ABDis congruent to△CDB(SSS)
∴ ∠ ADB=∠ CBDand ∠ ABD=∠ CDB(corr.∠s,congruent △)
b.∠ADM=∠CBM(proved)
∠ AMD=∠ CMB(vert. opp. angles)
AD=CB(given)
∴ △AMD is congruent to △CMB
∴ AM=CM and MD=MB(corr. sides,congruent△)
∴ACand BD bisect each other
2006-11-16 21:27:41 補充：
∴ △AMD is congruent to △CMB(AAS)
收錄日期: 2021-04-22 00:13:30
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20061116000051KK04038