Violympic toán 7
Các câu hỏi tương tự
6.a) tim 2 so x, ybik 7x=2y va x-y=16
b)so sanh a,b,c bik a/b=b/c=c/a
c)tim cac so a,b,cbik a/2=b/3=c/4 va a+2b-c=-20
d)cho x/2=y/5=z/7 tinh gia tri bieu thuc A=x-y+z/x+2y-z
e)cho 3x-2y/4=2z-4x/3=4y-3z/2.CMR x/2=y/3=z/4
f)cho a,b,c la cac so huu ti khac sao choa+b-c/c=a-b+c/b=-a+b+c/a
tinh gia tri bang so cua 1 bieu thuc m=(a+b)(b+c)(c+a)/abc
g)cho x/a=y/b=z/c CMRbz-cy/a=cx-az/b=ay-bx/c
Tim cac cap so nguyen x;y sao cho x^2+y^2=5
tim gia tri nguyen cua x de bieu thuc:x^2+7/x+1 cung nhan gia tri la so nguyen
tim a sao cho a la so chinh phuong va a chia het cho 153
1.ba nha kinh doanh hun von theo ti le 2:3:4tinh so tien lai moi nguoi bik so tien lai dc chia theo ti le hun von tong so tien lai 180 trieu dong
2.bik cu 100kg thoc thi cho 60 kg gao. Hoi 20 bao thoc moi bao nang 60 kg thi cho bn kg gao ??
3.de dao con muong can 30 nguoi lm trog 8 h . neu tang them 10 thoi gian giam dc may h? (nang suat nhau)
4. 2 xe o to tu A den B. van toc xe I la 60km/h. Van toc xe thu 2 la 40km/h. thoi gian xe I di it hon xe2 la 30 phut. Tinh thoi gian moi xe di tu A den...
Đọc tiếp
1.ba nha kinh doanh hun von theo ti le 2:3:4tinh so tien lai moi nguoi bik so tien lai dc chia theo ti le hun von tong so tien lai 180 trieu dong
2.bik cu 100kg thoc thi cho 60 kg gao. Hoi 20 bao thoc moi bao nang 60 kg thi cho bn kg gao ??
3.de dao con muong can 30 nguoi lm trog 8 h . neu tang them 10 thoi gian giam dc may h? (nang suat =nhau)
4. 2 xe o to tu A den B. van toc xe I la 60km/h. Van toc xe thu 2 la 40km/h. thoi gian xe I di it hon xe2 la 30 phut. Tinh thoi gian moi xe di tu A den B va chieu dai quang duong AB ?
5.ba doi may cay lm viec tren 3 canh dong co DT = nhau. Doi I hoan thanh cong viec trong 4 ngay, doi 2 trong 6 ngay , doi 3 trong 8 ngay. hoi moi doi co bn may( co cung nang suat)bik rang doi I nhieu hon doi 2 la 2 may?
6. cho ham so y=-2x
a. bik diem A(3:yo)thuoc dthi ham so y=-2x. tinh y mu 0
b. diemB(1,15:3) va C(1,5;-3) co thuoc dthi ham so y=-2x hay ko???
c.e do thi ham so y=-2x
a,ve do thi ham so y=3x
b,tim toa do diem A , biet A thuoc do thi ham so tren va A co tung do la 6
c,tim diem tren do thi sao cho diem do co tung do va hoanh do bang nhau
cho tam giac ABC ,M la trung diem AC tren tia doi tia MB lay diem D sao cho MB= MD
a,chung minh tam giac AMB bang tam giac CMD
b,tu A va C ha cac duong vuong goc xuong BD lan luot cat BD o K va H chung minh AK =CH
c,goi E la trung diem cua BC ,F la trung diem cua AD . chung minh 3 diem E,M,F thang hang
Cho tam giac ABC co AD va BE la cac duong trung tuyen cat nhau tai G . Biets AD=12CM , BE=9cm . Tinh do dai cua AG va GE
tim so nguyen a de : a^2 + 5a +4 / a + 5 la mot so nguyen