ΔABC = ΔDEF
\(\Rightarrow BC=FE=10\left(cm\right)\)
Chu vi ΔABC là :
\(AB+AC+BC=6+8+10=24\left(cm\right)\)
ΔABC = ΔDEF \(\Rightarrow\) Chu vi ΔABC = Chu vi ΔDEF
Vậy Chu vi ΔABC là 24 cm ;ΔDEF là 24 cm
Cho tam giac ABC = tam giac DEF. Biet goc A + goc B = 130 do, goc E = 55 do. Tinh cac goc cua moi tam giac.
cho tam giac ABC vuong tai A ,co AC=2AB.lay D la trung diem cua AC .dung AH,CK vuong goc voii BC.
a) cm; goc ABC = goc CDK va tam giac AHB = tam giac CKD
b) cm : DA= DC =DH va KH = KC
c) goi I la trung diem cua BD . Cm: tam giac AHI = tam giac KHI tu do tinh soo do goc IHK
d ) duong thang di qua A song song voi BC cat DK tai M. cm : H , I , M thang hang
e) duong thang AI cat BC tai N . cm : NK =
Cho tam giac abc co dla trung diem ab va ela trung diem ac . Ve f sao cho e la trung diem cua df
A) Cm bd=cf
B)cm tam giac bdc=tam giac fcd
C) cm de //bc va de =1/2bc
Cho tam giac abc can tai a.ve ah vuong goc voi bc tai h.cho ah=8 cm,bh=6 cm
a,tinh ab,ac
b,chung minh tam giac abh=tam giac ach
cho tam giac ABC can tai A goi E la trung diem cua AB goi F la trung diem cua AC CMR tam giac ABF bang tam giac ACE
CMR EF song song BC
cho tam giac ABC can tai A va tam giac DEF can tai D biet goc A bang 80 do goc E bang 50 do thi
Cho tam giac ABC vuong tai A co tia phan giac BD(\(D\in AC\)).Tren canh BC lay diem E sao cho AB=BE.Tren tia doi cua tia AB lay diem F sao cho AF=EC.Goi I la giao diem cua BD va FD.Chung minh rang
a)CM ΔABD=EBD, \(DE\perp BC\)
b)BD la duong trung truc cua doan AE
3)3 diem F,D,E thang hang
4)Tinh do dai doan FC khi AC = 5cm ,ACB = 30 do
Tinh cac goc cua mot tam giac , biet 3 goc cua tam giac ti le voi 1, 2 va 3.
Cho tam giác ABCco A=6cm,BC=8cm ,CÁ=10cm
a, Dinh dang tam giac ABC
b, Tren tia doi cua tia BC lay diem D sao cho BD=BC .Chung minh tam giac ACD can
c,Tren AB lay diem M .Chung minh rang MC=MD va MB la tia phan giac cua goc CMD
