cho tam giac ABC, D la trung diem cua BG.tren canh AD lay E sao cho AE = 2 lan ED. noi BE keo dai cat AC tai G . hay chung to rang G la trung diem cua AC.
cho hinh tam giac abc tren canh bc lay diem m sao cho mb = mc tren canh ac lay diem d sao cho ad= 1/3 ac
a) so sanh s abc va s cbd
b) goi I la trung diem cua ab boi bd. So sanh AID va s CID
Cho tam giac ABC. M la trung diem cua cach BC .Tren AC lay diem N sao cho AN =1/4 AC tai diem . Noi diem MN keo dai cat canh AB tai diem Q . Noi Q voi C . Cho biet dien tich AQN =10 . Tinh dien tich ABC
Cho tam giac ABC vuong tai C,CH la duong cao.Tren CH lay X bat ki (X khac C,H). Goi K,K1 la giao cua (B,BC) voi AX (K thuoc doan AX).Goi L,L1 la giao diem cua (A,AC) voi BX (L thuoc BX) . M la giao diem cua AL va BK. CMR tu giac KLK1L1 noi tiep
Nguon: HSG Hai Phong (2014-2015)
cho tam giac abc .tren canh ab lay diem m sao cho am gap ruoi mb tren canh ac lay diem n sao cho an bang 1 nua ac.biet dien tich tam giac amn la 36 cm vuong.tinh dien tinh tu giac bmnc
cho tam giac abc tren canh ab lay diem m,tren canh ac lay diem n so cho am bang 1/3 ab,nc=2/3 ac.hoi dien tich tam giac abc gap may lan tam giac amn
cho tam giac abcd tren canh ab lay diem m tren canh ac lay diem n sao cho an=1/3ac nc2/3ac dien tich abc gap dien tam giac anm so lan la
cho tam giac ABC tren canh AB lay diem M tren canh AC lay diem N sao cho AM=1/3AB NC=2/3AC dien tich tam giac ABC gap dien tich AMN so kan la
cho tam giac abc co goc a vuong , ab= 30cm , ac=45cm.M la 1 diem tren canh ab sao cho am=20cm. Tu M ke duong thang song song voi canh bc cat canh ac tai diem n.Hoi: a/ tinh S abc, b/ tinh S anm