cho doan thang AB bang 8cm C la motoem nam giua AvaB sao cho AC bang 3cm . Goi M la trung diem cua AC goi diem N la trung diem cua CB
a, hoi trong ba diem M,C,N diem nap nam giua 2 diem con lai vi sao
b, goi Ela trung diem cua MN . so sanh doan MN va EB
Trinh bay ro rang nhe . Minh dang can gap