Tmf a,b,c biết : 2009abc chia hết cho 315
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
3,9 haaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
![](https://rs.olm.vn/images/avt/0.png?1311)
Vì \(A=\overline{2009abc}⋮315\)
nên c=0 hoặc c=5
TH1: c=0
=>(a,b)=(0;7) hoặc (a,b)=(7;0) để A chia hết cho 9
TH2: c=5
=>(a,b)=(3;8) để A chia hết cho 9
\(\left(a,b,c\right)\in\left\{\left(0;7;0\right);\left(3;8;5\right);\left(7;0;0\right)\right\}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
x chia hết cho 35 , x chia hết cho 63 , x chia hết 105 nên x thuộc BC(35;63;105)
Ta có:
63=3^2x7
35=5x7
105=3x5x7
=>BCNN(35;63;105)=3^3x5x7=315
=>x thuộc B(315)
B(315)={0;315;630;945;...}
Mà 315 < x < 632 nên x=630
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
Bài 1:
a, \(92.4-27=\left(x+350\right):x+315\)
\(\Rightarrow\left(x+350\right).\dfrac{1}{x}=92.4-27-315\)
\(\Rightarrow1+\dfrac{350}{x}=26\)
\(\Rightarrow350:x=25\Rightarrow x=14\)
b, \(720:\left[41-\left(2x+5\right)\right]=2^3.5\)
\(\Rightarrow720:\left(41-2x-5\right)=8.5\)
\(\Rightarrow720:\left(36-2x\right)=40\)
\(\Rightarrow36-2x=18\Rightarrow2x=18\Rightarrow x=9\)
Chúc bạn học tốt!!!
1)
a)
\(92.4-27=(x+350):x+315\)
\(368-27=(x+350):x+315\)
\(341=(x+350):x+315\)
\((x+350):x=341-315=26\)
\(26x=x+350\)
\(25x=350\)
\(x=14\)
b)
\(720:[41-(2x+5)]=2^3.5\)
\(720:[41-(2x+5)]=40\)
\(41-(2x+5)=18\)
\(2x+5=23\)
\(2x=18\)
\(x=9\)