prove parallelogram.
2008-06-14 11:27 pm
回答 (2)
2008-06-15 1:23 am
✔ 最佳答案
AD=BC(given)∠ADB=∠DBC(givven)
BD=BD(given)
∴ΔADB is corngent to ΔCDB (S.A.S.)
∵ΔADB is corngent to ΔCDB
∴∠BCD=∠DAB
∴∠DBA=∠CDB(∠sum ofΔ)
∴∠DBA+∠CBD=∠CDB+∠ADB
∵∠BAD=∠DCB,∠ADC=∠CBA
∴AB//CD, AD//BC
∴ABCD is a parallelogram(definition of //gram)
參考: Myself
收錄日期: 2021-04-13 15:41:33
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080614000051KK01456