Các câu hỏi tương tự
cho tam giac ABC co AB=AB,goc B=goc C.Ke BD vuong goc voi AC va oe CE vuong goc voi AB.Hai doan thang BD va CE cat nhau tai I a)C/m tam giac BDC=tam giac CEB.b)so sanh goc IBE va goc ICD.c) duong thang AI cat BC tai trung diem H.c/m AI vuong goc voi BC
Cho tam giac ABC va diem M nam trong tam giac do. Tia AM cat BC tai D.
a. So sanh goc BAD va goc BMD
b. So sanh goc BAC va goc BMC
1)So vo duoc thuong cua 3 lop 7A ;7B ; 7C lan luot ti le voi 2;3;4 .Tinh so vo moi lop biet rang so vo cua lop 7A va 7c nhieu hon so vo cua lop 7B la 36 quyen
2) cho tam giac co goc abc = 60do;goc ACB=50do.Goi AD la tia phan giac goc BAC[D thuoc BC]
a)Tinh goc BAC;goc ADc
b)Qua B ke duong thang d song song voi AD ,d cat duopng thang AC tai M.Chung minh goc MBA = goc BMA
c)Goi Ax la tia phan giac cua goc BAM.Chung minh Ax vuong goc voi BM
cho tam giac ABC co goc ABC=30do va goc BAC=130do. goi Ax la tia doi cua tia AB, duong phan giac cua goc ABC cat phan giac cua goc CAx tai D. duong thang BA cat duong thang CD tai E. So sanh do dai AC va CE
cho tam giac ABC co goc ACB bang 60 do .a) ve tam giac ABC b) hai tia phan giac cua goc ABC va ACB cat nhau tai I . Qua I ve duong thang song song Bc , duong thang nay cat cac duong thang AB va AC tai D v E .Tinh so do goc ACI va goc CIEc) So sanh 2 goc DIB va ABI d) Qua A ke AH vuong goc voi BC tai H , qua C ke CK vuong goc voi DE tai K .Giai thic vi sao AH song song voi CK e) tinh so do goc CAHGIAI NHANH GIUM MINH NHA!!!MINH DANG CAN GAP ...
Đọc tiếp
cho tam giac ABC co goc ACB bang 60 do .
a) ve tam giac ABC
b) hai tia phan giac cua goc ABC va ACB cat nhau tai I . Qua I ve duong thang song song Bc , duong thang nay cat cac duong thang AB va AC tai D v E .Tinh so do goc ACI va goc CIE
c) So sanh 2 goc DIB va ABI
d) Qua A ke AH vuong goc voi BC tai H , qua C ke CK vuong goc voi DE tai K .Giai thic vi sao AH song song voi CK
e) tinh so do goc CAH
GIAI NHANH GIUM MINH NHA!!!MINH DANG CAN GAP ...
Cho tam giac ABC ( AC > AB ) tia phan giac cua goc BAC cat BC tai D. Tren canh AC lay diem E sao cho AE = AB
a) Chung minh BD = DE
b) Keo dai AB va DE cat nhau tai K . Chung minh goc ACD = goc AKD
c) Chung minh tam giac KBE = tam giac CEB
Cho tam giac ABC co goc ABC= 30do va BAC=130do. Goi Ax la tia doi cua tia AB, duong phan giac cua goc ABC cat phan giac cua goc CAx tai D. Duong thang BA cat duong thang CD tai E. So sanh do dai 2 canh AC va CE
hai duong thang xx' va yy' cat nhau tai diem o tao thanh 4 goc trong do hai goc x'oy va x'oy' bang 248 so do goc xoy' la
hai doan thang AB va CD cat nhau tai E. Cac tia phan giac cua cac goc ACD va ABD cat nhau tai K. Chung minh rang BKC = 1/2(CAE+BDE)