a-2b-5=0
3a+b+6+0
更新1:
3a+b+6=0
3a+b+6=0
收錄日期: 2021-04-24 23:24:48
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081123000051KK00919