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

ve 4 diem a,b,m,n thang hang sao cho: a, diem m nam giua 2 diem a va b , diem n nam giua 2 diem a va b b, diem b nam giua 2 diem a va n , diem n nam giua 2 diem a va b

Ve hinh theo cach dien dat sau:

a, diem M nam giua hai diem A va B: diem N khong nam giua hai diem A va B (ba diem N,A,B thang hang)

b, Diem B nam giua hai diem A va N; diem M nam giua hai diem A va B

ve : a) ba diem m,n,p thang hang .b)ba diem c,e,d thang hang sao cho diem e nam giua hai diem cvad .c)ba diem t,q,r khong thang hang

Lay 3 diem khong thang hang A,B,C ve hai tia AB,AC

Ve tia Ax cat duong thang BC tai diem M nam giua B va C

Ve tia Ay cat duong thang BC  tai diem N ko nam giua B,C

lay ba diem khong thang hang a,b,c .ve hai tia ab,ac.ve hai tia ab , ac

a, ve tia ay cat duong thang bc tai diem m nam giua b va c

b,ve tia ay cat duong thang bc tai diem n khong nam giua b va c

Cho 2 doan thang a , b cat nhau tia O , M thuoc q , M thuoc b 

a, hay ve diem A sao cho M nam giua O va A roi ve diem B sao cho B nam giua O va N

b, goi I la diem cua 2 doan thang AB va MN . Diem I nam giua 2 diem nao . Diem I co nam giua A va N khong

a/Cho ba diem A,B,C thang hang thi co may truong hop hinh ve?

b/Trong moi truong hop,co may diem nam giua hai diem con lai?

c/Hay noi cach ve ba diem khong thang hang

cho 3 diem A,B,C, khong thang hang,ve doan thang BC

ve diem M la trung diem cua doan thang BC

ve tia BA,duong thang AC

ve duong thang AD sao cho M nam giua A va D