CHO hinh ve biet Ax song song Cy . goc A =40 do , AB vuong goc  BC .Tinh goc BCI=?

cho goc xoy = 140 do , tren tia ox , lay diem a ve tia Az sao cho tia Az va tia oy nam tren cung 1 nua mat phang bo chua tia ox va goc oaz = 40 do . a) CMR Az song song oy b) ve tia Az' la tia doi cua tia Az . CMR 2 duong thang phan biet cua 2 goc xoy va goc oaz song song voi nhau

cho goc xoy = 140 do , tren tia ox , lay diem a ve tia Az sao cho tia Az va tia oy nam tren cung 1 nua mat phang bo chua tia ox va goc oaz = 40 do .

a) CMR Az song song oy

b) ve tia Az' la tia doi cua tia Az . CMR 2 duong thang phan biet cua 2 goc xoy va goc oaz song song voi nhau

Cau 1: So sanh cac chung toc lon tren the gioi ve hinh thai ben ngoai va noi sinh song tren the gioi

Cau2: phan biet quan cu nong thon va quan cu thanh thi

Cau 3: dan cu tren the gioi phan bo nhu the nao? Cho biet noi nao co dan cu tap tung dong?

Giup mk vs mai on tap kiem tra roi!

cho hai duong thang a va b song song. tren duong thang a lay 10 diem phan biet, tren duong thang b lay 15 diem phan biet. hoi co the ve bao nhieu duong thang phan biet  qua 2 trong cac diem da cho ?

bai 1. cho doan thang zz' cat 2 duong thang song song xx' va yy' thu tu tai A vaB . ve tia At la tia phan giac cua xAz' va tia BM la tia phan giac cua zBy'. CMR : At // BM

bai 2 cho tam giac ABC tren nua mat phang bo BC chua diem A ve tia Cx song song voi AB. Ve tia Cy la tia phan giac cua ACx. ve tia Az la tia phan giac cua BAC. CMR Cy // Az

Phat bieu Ve hinh va ghi gia thietb,ket luan ki hieu tinh chat 2 dg thang song song

Phat bieu ve hinh va ghi gia thiet, ket luan duoi dangki hieu dau hieu nhan biet 2dg thang sog song

Nhanh nhe cac ban

ve hinh theo cach dien dat sau:

a,ve hai duong thanh phan biet kong song song a va b

lay hai diem A va B sao cho A thuoc a, B thuoc b

c, ve duong thang c di qua B sao cho c vuong goc voi a

d, ve duong thang c di qua A sao cho d song song voi b

cho hinh ve :

biet A=140^o

B=70^o

C=150^o

chung minh : Ax//Cy