Các câu hỏi tương tự
cho tam giac ABC ( vuong o A ), duong cao AD. Lay E va F sao cho AB la trung truc cua DE va AC la trung truc cua DF
a) Chung minh rang: E,A,F thang hang
b) Hoi tam giac ABC can co them dieu kien nao de AE vuong goc AD
cho tam giac ABC vuong can tai A. Chung minh tia phan giac AD cua BAC chia doi goc tao boi duong cao AH va trung tuyen AM
cho tam giac abc duong trung tuyen bm va cn cua tam giac abc
a} chung minh bnmc la hinh thang
b} chung minh mn=1/2 bc
c} tinh chu vi hinh thang bnmc biet ab=5cm duong cao ah=3cm
Cho tam giac abc vuong tai a ke ah vuong goc voi bc tai h. Hoi a,chung minh tam giac abh bang tam giac ach , ve trung tuyen bm goi g la giao diem cua ah va bm cm g la trong tam abc c, cho ab= 30 bh=18 tinh ah ag d, tu h ke hc song song ac cm 3 diem cgd thang hang
Cho tam giac ABC n tai A co duong cao AH
a/ Chung minh tam giac ABH = tam giac ACH va AH la tia phan giac cua goc BAC
b/ Cho BH = 8 cm ; AB = 10 cm . Tinh AH
c/ Goi E la trung diem cua AC va G la giao diem cua BE va AH . Tinh HG
d/ Ve Hx song song voi AC, Hx cat AB tai E . Chung minh C,G,E thang hang
( giup minh voi nhe THANH YOU )
Cho tam giac ABC .Ke trung tuyen AM Tren tia doi cua tia MA lay diem E sao cho ME=MA
a,Chung minh tam giac AMB=tam giac ECM
b,Ke AH vuong goc voi BC. Ten tia doi cua tia HA lay diem D sao cho HD=HA.Chung minh :BCla tia phan giac cua goc ABD va BD=CE
c.Hai duong thang BD va CE cat nhau tai K. Chung minh :tam giac BCK can
Cho tam giac ABC,duong cao AD,Hla truc tam.Lay diem M bat ky thuoc canh BC,E va F thu tu la hinh chieu cua M tren AB,AC.Goi I la trung diem cua AM
a) Chung MInh EI=DF
b)Goi O la giao diem cua ID va EF,chung minh M,O,H thang hang
Lam jum nha minh .tk..... cho
Cho tam giác ABC co AB = 6cm, AC = 8cm: đường phân giác BI. Ke IH vuong goc BC (H thuoc BC). Goi k la giao diem cua AB va IH.
a) Tinh BC
b)Chứng minh : tam giácABI = tam giác HBI
c) Chung minh BI la duong trung truc cua doan thang AH
d)Chung minh: IA = IC
e)Chung minhI la truc tam cua tam giac ABC
cho tam giac ABC co AC>AB trung tuyen AM tren tia doi cua tia MA lay diem D sao cho MD=MAnoi C voi D
a) chung minh ADC>DAC tu do suy ra MAB>MAC
b) ke duong cao AH goi E la mot diemm nam giua A va H so sanh HC va HB