cho 5 diem A B C D E sao cho 3 diem a b c thang hang ba diem b c d thang hang ba diem b c e khong thang hang a) giai thich vi sao ba diem a b d thang hang? b)ke duong thang moi duong thang di qua it nhat 5 diem tren c)ke ten cac duong thang trong hinh ve
cho 2 duong thang A va B cat nhau tai O .Tren duong thang A lay 3 diem A,B,C theo thu tu do.Tren duong thang B lay 3 diem M,N,P theo thu tu do .Goi I la giao diem 2 doan thang AN va PM .Goi K la giao diem 2 doan thang AB va CM.Goi J la giao diem 2 doan thang CN va PB .
Ve tren cung mot hinh theo cach dien dat sau :
a)Ve 4 diem A ,B ,C D sao cho C nam giua A, B va 3 diem A, B D ko thang hang . Hay ve va ke ten duong thang (phan biet) di qua tung cap diem .
b) Ve diem E sao cho E va D nam khac phia doi voi A . Ve diem F sao cho C,E,F thang hang va F thuoc duong thang DB
1. Lay 4 diem A, B, C, D trong do khong co 3 diem nao thang hang. Ke cac duong thang di qua cac cap diem. Co bao nhieu duong thang tat ca? do la nhung duong thang nao?
2. Lay 4diem M,N,P,Q trong do 3 diem M,N,P thang hang va diem Q nam ngoai duong thang do. ke caacacc duong thang di qua cac cap diem. co bao nhieu duong thang phan biet? viet ten cac duong thang do
mong cac ban giai ho minh!
Cho doan thang d . Ve them 4 diem M,N ,P,Q theo thu tu ay . Ve diem A khong nam tren duong thang d.
a) Ve tia AM, tia QA
b)Ve duong thang AN va duong thang AP.
c) hinh tren co bao nhieu doan thang?
Cho cac diem a ,b,c,d,e trong do a,b,c cung thuoc duong thang m; cac diem c, d, e cung thuoc duong thang n va b, c, d la 3diem ko thang hang
cho duong thang xy va diem O nam tren duong thang xy tren tia Ox lay diem E sao cho OE=3cm.tren tia Oy lay diem G sao cho EG=6cm a)tren 3 diem O,E,G thi diem nao nam giua hai diem con lai ? vi sao b) tinh do dai doan thang OG. tu do cho biet diem O co la trung diem cua doan thang EG khong?
1. Tren 1 duong thang xy lay 4 diem phan biet A,B,C,D hay chi ra cac tia doi nhau
2. cho 10 diem trong do khong co ba diem thang hang . Cu qua hai diem ta ve duoc 1 duong thang . Hoi co tat ca bao nhieu duong thang?
3. cho n diem trong do khong co ba diem nao thang hang . Cu qua hai diem trong so cac diem do ve duoc 1 duong thang. Biet rang co 435 duong thang tao thanh .Tim n?
ve duong thang zy lay diem A nam tren duong thang zy.diem B khong nam tren duong thang di qua diem A va B
a,ke ten cac tia goc A
b,ke ten cac tia doi nhau trong hinh