cho tam giac abc can tai a duong cao ah =10 bk=12. bc?
Cho tam giac ABC vuong tai A, duong cao AH, phan giac BE cat nhau tai D. CD cat AB tai F. CMR BF.cos^2C = AF.sinC
CHO TAM GIAC ABC CAN TAI A VA DUONG CAO AD CO H LA TRUC TAM .TINH AD BIET AH=14CM, HB=HC=30CM
1.cho tam giac ABC co truc tam H, va N la trung diem BC va AC ; o la giao diem trung truc cua tam giac ABC. CMR:
a, tam giac OMN dong dang tam giac HAB. tim ti so dong dang
b, so sanh AH va OM
c, goi G la trong tam cua tam giac ABC. CM tam giac HAG dong dang tam giac OMG
d, H,G,O thang hang va HG=2GO
2. 1 duong thang di qua A cua hinh binh hanh ABCD cat BD,BC,CD lan luot tai E,K,G. CMR:
a, AE2 = KE . EG
b, \(\frac{1}{AE}\)=\(\frac{1}{AK}\)+\(\frac{1}{AG}\)
c, BK .DG khong doi khi duong thang thay doi quanh A
cho tam giac ABC vuong tai A duong cao AH tinh chu vi cua tam giac ABC biet AH=14cm HB/HC=1/4
1. Cho tam giac ABC vuong tai A phan giac AH biet CD =68cm, BD =51cm. Tinh BH,HC
2. Cho tam giac ABC vuong tai A duong cao AH biet AB=7,5cm ; AH=6cm.
a) Tinh AC,BC
b) Tinh cos B, cos C
CHO TAM GIAC ABC VUONG TAI A , DUONG CAO AH , CHO CHU VI TAM GIAC AHB=30cm , AHC=40cm . Tinh chu vi tam giac ABC
cho tam giac ABC vuong can o A va M la trung diem BC tren tia BC lay diem D voi D khac B va M ke BK vuong goc voi AD tai K chung minh rang KM la phan giac ngoai cua tam giac AKB tai K