cho doan thang AB = 5cm va diem C nam giua 2 diem A va B sao cho CB = 3cm
a, tinh do dai doan thang AC
b, tren tia doi cua tia CA lay diem D sao cho CD = 5cm hay so sanh AC va BD
cho doan thang AB dai 4 cm . tren tia AB lay diem C sao cho AC = 1cm
a, tinh CB
b, lay diem D thuoc tia doi cua tia BC sao cho BD = 2cm. tinh CD
ve doan thang MN dai 8 cm. goi R la trung diem cua MN.
a) tinh MR;RN
b) lay 2 diem P va Q tren doan thang MN sao cho NP=NQ=3cm. tinh RP ; RQ
c) diem R co la trugn diem cua doan thang PQ ko?
bai 1: tren tia Ox lay 2 diem A,B sao cho OA = 4 cm , OB = 7 cm
a) tinh AC
b) goi C la trung diem cua OA . tinh AC
c) tren tia doi cua tia Ox ,lay diem D sao cho OD=2cm. hoi O co la trung diem cua CD khong ? vi sao?
Cac ban nho ve hinh nha!
Bai 1: Cho doan thang AB=8cm . Tren tia AB lay diem M sao cho AM=4cm a) Diem Mco nam giua hai diem A va B khong ? Vi sao? b) So sanh AM va MB c) M co la trung diem cua doan thang AB khong?
Cac giai ho minh . Nho ve hinh nha !
Thank you very much
bai :2 tren tia Ox ve hai diem A,B sao cho OA = 5cm , OB = 3cm
a) ve hinh da cho
b) trong 3 diem O, A , B diem nao nam giua hai diem con lai ?vi sao
c) tinh AC
d) cho diem D tren tia Ox , sao cho B la trung diem cua OD . tinh AD
cho tam giac ABC co goc A vuong canh AB = 40m canh AC = 30m canh BC = 50m tren canh AC lay diem F tren canh AB lay diem E sao cho hinh thang EFCB co chieu cao la 12m tinh dien tich cua tam giac AEF va dien tich hinh thang EFCB ?
Cho tam giac ABC co BC=5cm . Diem D thuoc canh BC sao cho DC=2cm . Cho biet goc ADB=70o
a)Tinh do dai BD?
b)Tren nua mat phang chua A co bo BC , ve tia Dx sao cho goc CDx =50o.Tinh goc ADx?
c)Goi M la giao diem cua tia Dx va canh AC ,tim cac tam giac trong hinh ve
Tren nua mp cho tia Ox. Tren hai nua mp doi nhau co bo la Ox, ve hai tia Oy va Oz sao cho goc xOy= goc xOz=120°. Hay chung to rang :
a, goc xOy=xOz=yOz
b, Tia doi cua moi tia Ox, Oy, Oz la tia p/giac cua goc hop boi 2 tia con lai.