cho tam giac ABC goi D la trung diem cua AB tren tia doi cua tia DC lay diem M sao cho DM = DC goi E la trung diem cua AC tren tia doi cua tia EM lay diem N sao cho EN = EM
a) Chung minh AM = AN
b) M;A;N thang hang
c) A la trung diem cua MN
giup minh nhe cac ban minh can gap lam ( ve hinh cho minh luon nha cam on cac ban rat nhiu hihi!! )
nhanh nhanh cac ban oi giup minh di ma
co ai giup minh hk