a) \(\dfrac{5}{24}+x=\dfrac{7}{12}\)

<=> \(x=\dfrac{7}{12}-\dfrac{5}{24}=\dfrac{14}{24}-\dfrac{5}{24}=\dfrac{9}{24}=\dfrac{3}{8}\)

b) \(x-\dfrac{3}{4}=\dfrac{1}{2}\)

<=> \(x=\dfrac{1}{2}+\dfrac{3}{4}=\dfrac{2}{4}+\dfrac{3}{4}=\dfrac{5}{4}\)

c) bn ghi rõ đề chút

ok bạn

(2\7.x+3\7) :2 1\5-3\7=1

hai phần bảy nhân x cộng ba phần bảy chia hai một phần năm trừ 3 phần bảy bằng một

Giải:

a) \(\dfrac{5}{24}+x=\dfrac{7}{12}\) 

              \(x=\dfrac{7}{12}-\dfrac{5}{24}\) 

              \(x=\dfrac{3}{8}\) 

b) \(x-\dfrac{3}{4}=\dfrac{1}{2}\) 

            \(x=\dfrac{1}{2}+\dfrac{3}{4}\) 

            \(x=\dfrac{5}{4}\) 

c) \(\left(\dfrac{2}{7}.x+\dfrac{3}{7}\right):2\dfrac{1}{5}-\dfrac{3}{7}=1\) 

           \(\left(\dfrac{2}{7}.x+\dfrac{3}{7}\right):\dfrac{11}{5}=1+\dfrac{3}{7}\) 

           \(\left(\dfrac{2}{7}.x+\dfrac{3}{7}\right):\dfrac{11}{5}=\dfrac{10}{7}\) 

                        \(\dfrac{2}{7}.x+\dfrac{3}{7}=\dfrac{10}{7}.\dfrac{11}{5}\) 

                        \(\dfrac{2}{7}.x+\dfrac{3}{7}=\dfrac{22}{7}\)           

                                \(\dfrac{2}{7}.x=\dfrac{22}{7}-\dfrac{3}{7}\) 

                                \(\dfrac{2}{7}.x=\dfrac{19}{7}\) 

                                    \(x=\dfrac{19}{7}:\dfrac{2}{7}\) 

                                    \(x=\dfrac{19}{2}\)

\(\left|x+1\right|+\left|x-5\right|=3x+1\left(đk:x\ge-\dfrac{1}{3}\right)\)

\(\Leftrightarrow x+1+\left|x-5\right|=3x+1\)

\(\Leftrightarrow\left|x-5\right|=2x\)

\(\Leftrightarrow\left[{}\begin{matrix}x-5=2x\left(x\ge5\right)\\x-5=-2x\left(-\dfrac{1}{3}\le x< 5\right)\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-5\left(ktm\right)\\x=\dfrac{5}{3}\left(tm\right)\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}-x-1+5-x=3x+1\left(x< -1\right)\\x+1+5-x=3x+1\left(-1\le x< 5\right)\\x+1+x-5=3x+1\left(x\ge5\right)\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{3}{5}\left(ktm\right)\\x=\dfrac{5}{3}\left(tm\right)\\x=-5\left(ktm\right)\end{matrix}\right.\Rightarrow x=\dfrac{5}{3}\)

Lời giải:

$\frac{3}{8}+(x-\frac{5}{24}):\frac{1}{2}=1$

$(x-\frac{5}{24}):\frac{1}{2}=1-\frac{3}{8}=\frac{5}{8}$

$x-\frac{5}{24}=\frac{5}{8}\times \frac{1}{2}=\frac{5}{16}$

$x=\frac{5}{16}+\frac{5}{24}=\frac{25}{48}$

\(\frac{4}{5}.x-x-\frac{3}{2}.x+\frac{5}{6}=\frac{1}{2}-\frac{4}{3}\)đề nảy hả

\(\frac{4}{5}x-x-\frac{3}{2}x+\frac{5}{6}=\frac{1}{2}-\frac{4}{3}\) 

\(-\frac{1}{5}x-\frac{3}{2}x=-\frac{5}{6}-\frac{5}{6}\) 

\(-\frac{17}{10}x=-\frac{10}{6}\) 

\(x=\frac{50}{51}\)         

Bài làm:

Ta có: \(\frac{4}{5}x-x-\frac{3}{2}x+\frac{5}{6}=\frac{1}{2}-\frac{4}{3}\)

\(\Leftrightarrow-\frac{17}{10}x=-\frac{5}{3}\)

\(\Rightarrow x=\frac{50}{51}\)

|x+3/5|-1/2=1/2

|x+3/5|=1/2+1/2

|x+3/5|=1

=>x+3/5=1

x=1-3/5

x=2/5

hay

x+3/5=-1

x=(-1)-3/5

x=-8/5

Vậy x=2/5 hay-8/5

1)vì |x-4/5|=3/4 =>x-4/5=3/4 hay x-4/5=-3/4 x=3/4+4/5 x= -3/4+4/5 x=31/20 x=1/20 vậy x=31/20 hay 1/20

6-|1/2-x|=2/5

|1/2-x|=6-2/5

|1/2-x|=28/5

=>1/2-x=28/5

x=1/2-28/5

x=-51/10

hay

1/2-x=-28/5

x=1/2-(-28/5)

x=61/10

vậy x=-51/10hay61/10