Cho tam giac ABC.Ke duong phan giac trong va ngoai cua goc B cat AC tai I va D ke duong thang song song voi BC cat AB o M va N;a)Tinh AB va MN biet MI=12,BC=20,b)Tu C ke duoc song song AB cat IB tai E cat BC.CMR BI*IC=AI*IE va CE=CF

cho 2 phan so co tong bang -3 va tich bang 12/5 tinh tong cac so ngich dao cua 2 phan so

Cho 2 phan so co tong bang -3 va tich bang 12/5. Tinh tong cac so nghich dao cua 2 phan so do

Muon do be tong, nguoi ta tron 1 ta xi mang,2 ta cat, va 6 ta soi

a)tinh ti so phan tramtung thanh phan cua be tong

b)dung bieu do o vuong bieu dien cac ti so phan tram do

1.cho hai phan so co tong bang -3 va tich bang 12/5. tinh tong cac nghich daao cua hai phan so do

2.cho hai phan so toi gian a/b va c/d. biet a/b+c/d E z. chung minh /b/=/d/

Tinh tong cua cac phan so bang 28/63 ma co tu va mau deu la so co 3 chu so ai lam nhanh va dung mik tk cho

cho hình thang abcd có

ab=12 cm.dc=25cm.ah=8cm tinh

a,s hai hinh tam giac adc va abc

b,ti so phan tram s tam giac abc va adc

ai nhanh mk tick

Phan so thu nhat la 4/5, phan so 2/7. Tinh tong,hieu,tich,thuong cua phan so thu nhat va phan so thu hai

3/2.5+3/5.8+3/8.11+....+3/...?

Tinh phan ...? biet rang khoang cach o giua la 10 so

Va cho biet qui luat(y la cong thuc) de tinh phan...?

va tinh tong