Cho goc xOy=120 do va Ot la tia phan giac cua goc do tren tia Oy lay diem A qua A dung duong thang At' song song voi Ot a) Tinh goc yAt' b) Tu A dung duong thang Ax' song song voi Ox so sanh goc t'Ax' va goc tOx
cho xOy = 120 do va Ot la tia phan giac cua goc do.tren tia Oy lay diem A ,qua A dung dthang At'//Ot
a tinh goc yAt'
b TU A dung duong thang Ax'//Ox.so sanh 2 goc t'Ax' va tOx
Cho goc xOy, ve tia phan giac Ot cua goc xOy, tren tia Ot lay diem M bat ky, tren cac tia Ox, Oy lan luot lay cac diem A, B sao cho OA=OB.
goi H la giao diem cua AB va ot. CM:
a) MA= MB
b) OM la duong trung truc cua AB
c) biet AB= 6cm, OA= 5cm. tinh OH ?
d) goi C la giao diem cua AM va tia Oy, D la giao diem cua BM va tia Ox. CM: AB//CD
Bài1: cho góc xOy va tia phan giac Ot. Trên tia Ot lay điểm M bat ky ; tren cac tia Õ va Oy lan lupt lay cac diem A va B sao co OA = OB; goi H la giao diem cua AB va Ot. C/m
a) MA=MB
b) OM la duong trung truc cua AB
c) Cho biet AB= 6cm, OA= 5cm. Tinh OH
cho XOY =60 .diem A thuoc tia Ox .Qua A dung tia Ay' // Oy va nam trong xOy .Goi Ot va At' la phan giac xOy va xAy.
a)Tinh xAy'.
b)Tinh xAt'
c)chung minh Ot//At'
Ve goc xOy < 90ova tia phan giac Ot. Lay diem A thuoc Ox va B thuoc Oy sao cho OA=OB. C la diem bat ky tren Ot
1, CM tam giac CAB can
2, OC cat AB o D. Tinh goc ADO
cho xOy =120 do , ve tia oz nam giua 2 tia ox va oy sao cho xOz=24 do. goi tia ot la tia phan giac yOz . tinh xOt
cho goc xoy =50 do. lay diem A tren tia ox . tren cung 1 nua mat phang bo ox chua tia oy, ve tia ot sao cho oy cat nhau tai B va goc oAt =80 do. goi at' la tia phan giac cua goc xAt
a) chung minh At'song song voi Oy
b) tren nua mat phang ko chua diem A bo duong thang oy ve tia Bn song song Ox
tren duong thang xy lay diem o ve tia ot sao cho goc xot bang 30 . tren nua mat bo xy khong chua ot ve tia oz sao cho goc xoz = 120. ve tia ot' la tia phan giac cua goc yoz chung to rang goc xot va got yot' la hai goc doi dinh
ai lam nhanh minh tich cho