四邊形OABC頂點為O(0,0),A(a,0),B(a,a)和C(0,a)
如何求證OABC是正方形?
收錄日期: 2021-04-23 00:10:39
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20061024000051KK02016