![](https://rs.olm.vn/images/avt/0.png?1311)
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)
\(\left[\left(2x-11\right):3+1\right].5=20\\\left(2x-11\right):3+1=20:5\\ \left(2x-11\right):3+1=4\\ \left(2x-11\right):3=4-1\\ \left(2x-11\right):3=3\\ 2x-11=3.3\\ 2x-11=9\\ 2x=11+9\\ 2x=20\\ x=20:2\\ x=10 \)
<=> (2X-11):3+1=20:5
<=> (2X-11):3=4-1
<=> 2X-11=3x3
<=> 2X-11=9
<=> 2X=9+11
<=>X=20:2
<=> X=10
![](https://rs.olm.vn/images/avt/0.png?1311)
a) x= 10; y = 25
b) x + 2 y + 10 = 1 5 => ( x = 2).5 = ( y = 10).1=> 5.x + 10 = y + 10
=> 5.x = y mà y – 3.x = 2
Nên x = 1; y = 5
c) x = 20 ; y = 25
![](https://rs.olm.vn/images/avt/0.png?1311)
1) \(\frac{x}{2}=\frac{y}{3}=\frac{z}{7}=\frac{2x-4y+3z}{2.2-4.3+3.7}=\frac{-39}{13}=-3\)
\(\Leftrightarrow\hept{\begin{cases}x=-3.2=-6\\y=-3.3=-9\\z=-3.7=-21\end{cases}}\)
2) \(9x=10y\Leftrightarrow\frac{x}{10}=\frac{y}{9},4y=3z\Leftrightarrow\frac{y}{9}=\frac{z}{12}\)
suy ra \(\frac{x}{10}=\frac{y}{9}=\frac{z}{12}=\frac{x-y+z}{10-9+12}=\frac{78}{13}=6\)
\(\Leftrightarrow\hept{\begin{cases}x=6.10=60\\y=6.9=54\\z=6.12=72\end{cases}}\)
3) \(3x=4y=6z\Leftrightarrow\frac{x}{4}=\frac{y}{3}=\frac{z}{2}=\frac{x-y+z}{4-3+2}=\frac{-9}{3}=-3\)
\(\Leftrightarrow\hept{\begin{cases}x=-3.4=-12\\y=-3.3=-9\\z=-3.2=-6\end{cases}}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
2x + 4y = 94
2x + 2y + 2y =94
2 . ( x + y ) + 2y = 94
Vì x + y = 35
\(\Rightarrow\)2 . 35 + 2y = 94
70 + 2y = 94
2y = 94 - 70
2y = 24
\(\Rightarrow\)y = 24 : 2
\(\Rightarrow\)y = 12
thay y vào ta được :
x + 12 = 35
\(\Rightarrow\)x = 35 - 12
\(\Rightarrow\)x = 23
vậy x = 23 ; y = 12
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
Ta có: \(\hept{\begin{cases}3x=4y;2y=5z\\2x-3y+z=8\end{cases}\Rightarrow\hept{\begin{cases}\frac{x}{4}=\frac{y}{3};\frac{y}{5}=\frac{z}{2}\\2x-3y+z=8\end{cases}}}\) \(\Rightarrow\frac{x}{20}=\frac{y}{15}=\frac{z}{6}\Rightarrow\frac{2x-3y+z}{40-45+6}=\frac{8}{1}=8\)
Vậy : \(x=8.20=160;y=8.15=120;z=8.6=48\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) ta có: \(\frac{2x}{5}=\frac{4y}{3}=\frac{3z}{10}\Rightarrow\frac{1}{12}\cdot\frac{2x}{5}=\frac{1}{12}\cdot\frac{4y}{3}=\frac{1}{12}\cdot\frac{3z}{10}\)
\(=\frac{x}{30}=\frac{y}{9}=\frac{z}{40}\)
ADTCDTSBN
...
rùi bn tự lm típ nha