Contact us
Choose a category below so we can get back to you as quickly as possible.
證明:連接DM,BN.∵四邊形ABCD是平行四邊形,∴OA=OC,OB=OD,又∵M、N分別是OA、OC的中點,∴OM=ON又∵OB=OD∴四邊形BMDN是平行四邊形,∴BM‖DN且BM=DN.
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.