![](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)
Ta có : 2x + 12 = 3 . ( x - 7 )
2x + 12 = 3x - 3 . 7
2x + 12 = 3x -21
2x + 12 + 21 = 3x
2x + 33 = 3x
33 = 3x - 2x
x = 33
\(2x+12=3\left(x-7\right)\)
\(\Leftrightarrow\)\(2x+12=3x-21\)
\(\Leftrightarrow\)\(3x-2x=12+21\)
\(\Leftrightarrow\)\(x=33\)
Vậy \(x=33\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(\left|\frac{5}{4}x-\frac{7}{2}\right|-\left|\frac{5}{8}x+\frac{3}{5}\right|=0\)
\(\Rightarrow\hept{\begin{cases}\left|\frac{5}{4}x-\frac{7}{2}\right|=0\\\left|\frac{5}{8}x+\frac{3}{5}\right|=0\end{cases}}=\hept{\begin{cases}\left|\frac{5}{4}x\right|=\frac{7}{2}\\\left|\frac{5}{8}x\right|=\frac{-3}{5}\end{cases}=\hept{\begin{cases}x=\frac{14}{5}\\x=\frac{-24}{25}\end{cases}}}\)
b) \(\left|\frac{7}{8}x+\frac{5}{6}\right|-\left|\frac{1}{2}x+5\right|=0\)
\(\Rightarrow\hept{\begin{cases}\left|\frac{7}{8}x+\frac{5}{6}\right|=0\\\left|\frac{1}{2}x+5\right|=0\end{cases}}=\hept{\begin{cases}\left|\frac{7}{8}x\right|=\frac{-5}{6}\\\left|\frac{1}{2}x\right|=-5\end{cases}}\Rightarrow\hept{\begin{cases}x=\frac{-20}{21}\\x=\frac{-5}{2}\end{cases}}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
1. a) 4/7 x y - 2/3 = 1/5
4/7 x y = 1/5 + 2/3
4/7 x y = 3/15 + 10/15
4/7 x y = 13/15
y = 13/15 : 4/7
y = 91/60 ( nếu phải đổi thành hỗn số thì = 1 và 31/60 )
b) 2/9 - 7/8 x y = 1/3
7/8 x y = 2/9 - 1/3
7/8 x y = 2/9 - 3/9
7/8 xy = -1/9
y = -1/9 : 7/8
y = -8/63
c) 4/5 + 5/7 : x = 1/6
5/7 : x = 1/6 - 4/5
5/7 : x = 5/30 - 24/30
5/7 : x = -19/30
x = 5/7 : -19/30
x = -150/133 ( hốn số = -1 và 17/133)
Chúc bạn học tốt~
![](https://rs.olm.vn/images/avt/0.png?1311)
1,\(\left(\frac{7}{2}-2x\right).\frac{4}{3}=\frac{22}{3}\)
\(x.\left(\frac{7}{2}-2\right)=\frac{22}{3}:\frac{4}{3}=\frac{22}{3}.\frac{3}{4}=\frac{11}{2}\)
\(x.\frac{3}{2}=\frac{11}{2}\)
\(x=\frac{11}{2}:\frac{3}{2}=\frac{11}{2}.\frac{2}{3}=\frac{11}{3}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a)*=1
b)*=8
c)*=-155 ( -155 chứ không thể 155 được
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\frac{x}{3}=\frac{3}{x}\)
\(\Rightarrow x.x=3.3\)
\(\Rightarrow x^2=\left(\pm3\right)^2\)
\(\Rightarrow x=\pm3\)
\(\Rightarrow x\in\left\{3;-3\right\}\)
chúc bạn học tốt !!!
\(\frac{x}{3}=\frac{3}{x}\)
\(\Leftrightarrow x.x=3.3=9\)
\(\Leftrightarrow x^2=3^2=\left(-3\right)^2\)
\(\Leftrightarrow\orbr{\begin{cases}x=-3\\x=3\end{cases}}\)
Vậy..
hok tốt!!
\((x-3)(2x-7)=0\)
\(\Rightarrow\orbr{\begin{cases}x-3=0\\2x-7=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=3\\x=\frac{7}{2}\end{cases}}\)
Vậy \(x\in\left\{3;\frac{7}{2}\right\}\)
\(\left(x-3\right)\left(2x-7\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-3=0\\2x-7=0\end{cases}\Rightarrow}\orbr{\begin{cases}x=3\\x=\frac{7}{2}\end{cases}}\)
Vậy ...