cho 3 diem thang hang c,d,e hoi hai diem nao nam giua 2 diem con lai neu cd+ce=de
cho ba diem C,D,E thang hang,biet CD=2,5cm,DE=8cm,CE=5,5cm.hoi trong ba diem C,D,E diem nao nam giua hai diem con lai
Vì điểm E nằm giữa 2 điểm D và C nên ta có
8 - 5,5 = DC hay DC = 3,5
Trong điểm D,C,E thì điểm C nằm giữa 2 điểm D và E
cho 3 diem C D E biet CD=6cm CE=5cm DE=4cm hoi trong 3 diem diem nao nam giua 2 diem con lai
bai 1 : cho 3 diem V, A , T thang hang . diem nao nam giua 2 diem con lai neu :
TV + VA = TA
bai 2 : tren 1 duong thang , hay ve 3 diem V , A , T sao cho TA = 1 cm , VA = 3 cm . hoi diem nao nam giua 2 diem con lai
Cho 3 diem V,A,T thang hang . Diem nao nam giua hai diem con lai neu :
TV + VA =TA
cho ba diem v,a,t thang hang . diem nao nam giua hai diem con lai neu:
tv + va=ta
Cau 5: Trong cac khang dinh sau, khang dinh nao dung, khang dinh nao sai?
1.Ba diem phan biet la ba diem thang hang.
2.Voi ba diem phan biet luon co hai diem nam ve cung phia doi voi diem con lai.
3.Voi ba diem thang hang phan biet luon co hai diem nam khac phia voi diem con lai.
4.Voi ba diem A,B,C thang hang thi diem B luon nam giua hai diem A,C.
5.Co mot va chi mot duong thang di qua hai diem (phan biet) cho truoc.
6.Hai duong thang phan biet thi song song voi nhau.
7.Hai tia chung goc thi cung nam tren mot duong thang.
8.Hai tia chung goc thi doi nhau
9.Neu diem M nam giua diem A,B thi no la trung diem cua doan thang AB.
10.Neu MA=MB thi M la trung diem cua doan thang AB.
11.Neu MA+MB= AB va MA=MB thi M la trung diem cua doan thang AB.
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cho 100 diem thang hang hoi co bao nhieu diem nam giua hai diem con lai
Ve 5 diem A,B,C,D sao cho 3 diem A,B,C thang hang, 3 diem B,C,D thang hang, 3 diem C,D,E khong thang hang
a) Giai thich vi sao 3 diem A,B,D thang hang
b) Tren hinh ve hay tim diem nam giua 2 diem con lai
tren tia Oa ve doan thang OC = 2,5 cm ,OD =5cm.trong ba diem O,C,D diem nao nam giua hai diem con lai vi sao?hay so sanh OC va OD. neu OD =a cm ,Cla trung diem cua OD thi do dai doan thang CD bang bao nhieu ?
a: Trên tia Oa, ta có: OC<OD
nên điểm C nằm giữa hai điểm Ovà D
b: Ta có: C nằm giữa O và D
nên CO+CD=OD
hay CD=2,5cm
c: Ta có: C nằm giữa O và D
mà CO=CD
nên C là trung điểm của OD