更新1:
so dus that mean... if a line is drawn from the point to the line, then it must be perpendicular to the line?
so dus that mean... if a line is drawn from the point to the line, then it must be perpendicular to the line?
收錄日期: 2021-04-26 13:05:53
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090325000051KK00922