Figure in there：http://wenwen.sogou.com/z/ShowMaskQuestion.e?sp=586357320&sp=Sopenhelp
I need explain and reason！
Is AB // CD?give the reason
2014-07-24 11:06 pm
回答 (1)
2014-07-29 10:53 pm
✔ 最佳答案
Your figure cannot be seen.I include below the three conditions that you can show a pair of straight lines to be parallel.
圖片參考：https://s.yimg.com/rk/HA00430218/o/800290803.png
收錄日期: 2021-04-16 17:05:50
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140724000051KK00082