Các câu hỏi tương tự
cho tam giac ABC co goc B = 80 do, goc C =30 do . tia phan giac cua goc A cat BC o D . tinh doc ADC, goc ADB
cho tam giac ABC co goc A = 90 do va BC = 2 * AB ; E la trung diem cua BC . tia phan giac cua goc B cat canh AC o D
A ) chung minh DB la phan giac cua goc ADE
B ) chung minh BD = DC
C) tinh goc B , goc C cua tam giac ABC
CHO TAM GIAC ABC CO AD LA PHAN GIAC CUA GOC A (D THUOC BC). KE DEVUONG GOC VOI AB, KE DF VUONG GOC VOI AC
a, CHUNG MINH TAM GIAC AED= TAM GIAC AFD
b, TIA FD CAT TIA AB TAI P, TIA ED CAT TIA AC TAI Q. CHUNG MINH AP=AQ
c, TIA AD CAT PQ TAI M. CHUNG MINH AM LA DUONG TRUNG TRUC CUA DOAN THANG PQ
d, CHO GOC BAC=50 DO. TINH SO DO GOC APQ VA GOC AQP
cho tam giac ABC co B-C=a, tia phan giac cua goc A cat CB tai D. Cau a : tinh ADC,ADB . Cau b: ve AH vuong goc voi BC, tinh HAD
cho tam giac ABC co A=60 cac tia phan giac cua goc B va C cat nhau tai I,cat cac canh AC,AB lan luot tai D vaE tia phan gia cua goc BIC cat BC o F tinh goc BIC
cho tam giac ABC vuong tai a co goc B =60 do .tia phan giac cua goc B cat Ac o D ke K vuong goc voi Bd o k
a, tinh goc ABD,goc ACD Cm:tam giac BCD can
b,AB=CK
c,CM:tam giacAKB= tam giac KAC
cho tam giac abc co goc b = goc c, tia phan giac cua goc a cat bc tai d
1. chung minh tam giac adb = tam giac adc
2. chung minh ad vuong goc voi bc
3. tren tia doi cua tia da lay diem m sao cho da = dm, chung minh ab // cm
1)cho tam giac abc co goc b=goc c.goi i la trung diem cua canh bc.tren canh ab laydiem d,tren tia di lay diem e sao cho i la trung diem de.cm:
a,bd=ce;
b,cb la tia phan giac cua goc ace
cho tam giac ABC co goc A=90 do va AB=AC.Tren canh AB,AC lay tuong ung 2 diem D va E sao choAD=AE.Tu A va D ke duong vuong goc voi BE cat BC tai M va N.Tia ND cat CA o I.CM:
a,A la trung diem cua CI.
b,CM=MN
cho tam giac ABC co 3 goc nhon . ke AH vuong goc vs BC. lay cac diem D va E sao cho AB la duong trung truc cua HD, AC la duong trung truc cua HE . doan thang DE cat AB o I , cat AC o K. CHUNG MINH
a) goc DAE= 2 goc BAC
b) HA la tia phan giac cua IHK
C) goc BAC = goc IHB