a. 2,15-x=3,05
b. 0,12-(2x-5)=1,88\(\)
c. 1,74-3,5:x=1,24
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)
a) \(\left|x-1,7\right|+\dfrac{1}{2}=23\)
\(\left|x-1,7\right|=22,5\)
\(\Rightarrow x-1,7=\pm22,5\)
\(\Rightarrow x=\left\{24,2;-20,8\right\}\)
b) \(\left|x+\dfrac{4}{15}\right|-\left|3,75\right|=-\left|2,15\right|\)
\(\left|x+\dfrac{4}{15}\right|-3,75=-2,15\)
\(\left|x+\dfrac{4}{15}\right|=-2,15+3,75\)
\(\left|x+\dfrac{4}{15}\right|=1,6\)
\(\Rightarrow x+\dfrac{4}{15}=\pm1,6\)
\(\Rightarrow x=\left\{\dfrac{4}{3};-\dfrac{28}{15}\right\}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(\dfrac{1,2}{x+3}=\dfrac{5}{4}\)
\(\Rightarrow\left(x+3\right).5=1,2.4\)
\(\Rightarrow\left(x+3\right).5=4,8\)
\(\Rightarrow x+3=4,8:5\)
\(\Rightarrow x+3=0,96\)
\(\Rightarrow x=-2,04\)
vậy \(x=-2,04\)
b)\(\dfrac{3}{5}:\dfrac{2x}{15}=\dfrac{1}{2}:\dfrac{4}{5}\)
\(\Rightarrow\dfrac{3}{5}:\dfrac{2x}{15}=\dfrac{5}{8}\)
\(\Rightarrow\dfrac{2x}{15}=\dfrac{3}{5}:\dfrac{5}{8}\)
\(\Rightarrow\dfrac{2x}{15}=\dfrac{24}{25}\)
\(\Rightarrow15.24=\left(2x\right).25\)
\(\Rightarrow360=\left(2x\right).25\)
\(\Rightarrow360:25=2x\)
\(\Rightarrow14,4=2x\)
\(\Rightarrow x=7,2\)
vậy \(x=7,2\)
\(a,\dfrac{1,2}{x+3}=\dfrac{5}{4}\\ \left(x+3\right).5=1,2.4\\ 5x+8=4,8\\ 5x=4,8-8\\ 5x=-3,2\\ x=-3,2:5=-0,64\)
\(b,\dfrac{3}{5}:\dfrac{2x}{15}=\dfrac{1}{2}:\dfrac{4}{5}\\ \dfrac{2x}{15}=\dfrac{3}{5}\cdot\dfrac{4}{5}:\dfrac{1}{2}\\ \dfrac{2x}{15}=\dfrac{12}{25}.2\\ \dfrac{2x}{25}=\dfrac{24}{25}\\ 2x=\dfrac{24}{25}.5\\ 2x=\dfrac{24}{5}\\ x=\dfrac{24}{5}\cdot\dfrac{1}{2}=\dfrac{12}{5}\)
\(c,-\dfrac{4}{2,5}:3,5=1,5:x\\ x=3,5.1,5:\left(-\dfrac{4}{25}\right)\\ x=\dfrac{21}{4}\cdot\left(-\dfrac{25}{4}\right)=-\dfrac{525}{16}\)
\(d,0,12:3=2x:\dfrac{3}{5}\\ 2x=0,12\cdot\dfrac{3}{5}:3\\ 2x=\dfrac{9}{125}\cdot\dfrac{1}{3}\\ 2x=\dfrac{3}{125}\\ x=\dfrac{3}{125}\cdot\dfrac{1}{2}=\dfrac{3}{250}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) /x+\(\frac{4}{15}\)/ - / -3,75/ = -2,15
=> \(\orbr{\begin{cases}x+\frac{4}{15}+3,75=-2,15\\x+\frac{4}{15}+3,75=2,15\end{cases}}\)
=> ....v.....v giải ra ( từng th )
bài khác tương tự
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\frac{1}{2}x+\frac{1}{5}x+\frac{3}{5}=0\)
=> \(\left(\frac{1}{2}+\frac{1}{5}\right)x+\frac{3}{5}=0\)
=> \(\frac{7}{10}x+\frac{3}{5}=0\)
=> \(\frac{7}{10}x=-\frac{3}{5}\)
=> \(x=\left(-\frac{3}{5}\right):\frac{7}{10}=\left(-\frac{3}{5}\right)\cdot\frac{10}{7}=\left(-\frac{3}{1}\right)\cdot\frac{2}{7}=-\frac{6}{7}\)
b) \(\left|2\frac{1}{2}+x\right|-\left(-\frac{2}{3}\right)=3\)
=> \(\left|\frac{5}{2}+x\right|+\frac{2}{3}=3\)
=> \(\left|\frac{5}{2}+x\right|=\frac{7}{3}\)
=> \(\orbr{\begin{cases}\frac{5}{2}+x=\frac{7}{3}\\\frac{5}{2}+x=-\frac{7}{3}\end{cases}}\Rightarrow\orbr{\begin{cases}x=-\frac{1}{6}\\x=-\frac{29}{6}\end{cases}}\)
c) \(\left|x+\frac{4}{15}\right|-\left|-3.75\right|=-\left|-2,15\right|\)
=> \(\left|x+\frac{4}{15}\right|-3,75=-2,15\)
=> \(\left|x+\frac{4}{15}\right|=\frac{8}{5}\)
=> \(\orbr{\begin{cases}x+\frac{4}{15}=\frac{8}{5}\\x+\frac{4}{15}=-\frac{8}{5}\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{4}{3}\\x=-\frac{28}{15}\end{cases}}\)
a, \(\frac{1}{2}x+\frac{1}{5}x+\frac{3}{5}=0\Leftrightarrow\frac{7}{10}x+\frac{3}{5}=0\Leftrightarrow x=-\frac{6}{7}\)
b, đề sai
c, \(\left|\frac{x+4}{15}\right|-\left|-3,75\right|=-\left|-2,15\right|\)
\(\Leftrightarrow\frac{x+4}{15}-3,75=-2,15\Leftrightarrow\frac{x+4}{15}=\frac{8}{5}\Leftrightarrow x+4=24\Leftrightarrow x=28\)
![](https://rs.olm.vn/images/avt/0.png?1311)
`2,15-x=3,05`
`x=2,15-3,05`
`x=-0,9`
Vậy `x=-0,9`
__________________
`0,12-(2x-5)=1,88`
`2x-5=0,12-1,88`
`2x-5=-1,76`
`2x=-1,76+5`
`2x=3,24`
`x=3,24:2`
`x=1,62`
Vậy `x=1,62`
__________________
`1,74-3,5:x=1,24`
`3,5:x=1,74-1,24`
`3,5:x=0,5`
`x=3,5:0,5`
`x=7`
Vậy `x=7`
2,15−x=3,052,15-x=3,05
x=2,15−3,05x=2,15-3,05
x=−0,9x=-0,9
Vậy x=−0,9x=-0,9
__________________
0,12−(2x−5)=1,880,12-(2x-5)=1,88
2x−5=0,12−1,882x-5=0,12-1,88
2x−5=−1,762x-5=-1,76
2x=−1,76+52x=-1,76+5
2x=3,242x=3,24
x=3,24:2x=3,24:2
x=1,62x=1,62
Vậy x=1,62x=1,62
__________________
1,74−3,5:x=1,241,74-3,5:x=1,24
3,5:x=1,74−1,243,5:x=1,74-1,24
3,5:x=0,53,5:x=0,5
x=3,5:0,5x=3,5:0,5
x=7x=7
Vậy x=7