\(\left(-\frac{2}{3}:-\frac{1}{3}\right).\left(-\frac{9}{2}\right)-\frac{1}{4}< \frac{x}{8}< -\frac{1}{2}.\frac{3}{4}:\frac{1}{8}+1\)

\(2.\left(-\frac{9}{2}\right)-\frac{1}{4}< \frac{x}{8}< \left(-3\right)+1\)

\(\left(-9\right)-\frac{1}{4}< \frac{x}{8}< \left(-2\right)\)

\(\left(-\frac{37}{4}\right)< \frac{x}{8}< \left(-2\right)\)

\(-\frac{74}{8}< \frac{x}{8}< -\frac{16}{8}\)

            Vậy -74<x<-16

\(\frac{4}{3}.\left(\frac{1}{6}-\frac{1}{2}\right)=\frac{4}{3}.\frac{-1}{3}=\frac{-4}{9}\)

 k nha

\(\frac{-4}{9}\)k mk nha

\(\frac{4}{3}.\left(\frac{1}{6}-\frac{1}{2}\right)\)

\(=\frac{4}{3}.\left(\frac{1}{6}-\frac{3}{6}\right)\)

\(=\frac{4}{3}.\frac{-2}{6}\)

\(=\frac{4}{3}.\frac{-1}{3}\)

\(=\frac{-4}{9}\)

Câu 1,

x+y=-1/3 ; y+z=5/4 ; x+z= 4/3

=> 2(x+y+z)=9/4

=> x+y+z=9/8

Ta lại có: x+y=-1/3

=> z=9/8 -(-1/3)=35/24

Ta lại có: z+y=5/4

=> y=-5/24

=> x=.....

Câu 2:

\(-4\le x\le-\frac{11}{18}\)

a)

\(\begin{array}{l}\frac{2}{9}:x + \frac{5}{6} = 0,5\\\frac{2}{9}:x = \frac{1}{2} - \frac{5}{6}\\\frac{2}{9}:x = \frac{3}{6} - \frac{5}{6}\\\frac{2}{9}:x = \frac{{ - 2}}{6}\\x = \frac{2}{9}:\frac{{ - 2}}{6}\\x = \frac{2}{9}.\frac{{ - 6}}{2}\\x = \frac{{ - 2}}{3}\end{array}\)                        

Vậy \(x = \frac{{ - 2}}{3}\).

b)

\(\begin{array}{l}\frac{3}{4} - \left( {x - \frac{2}{3}} \right) = 1\frac{1}{3}\\x - \frac{2}{3} = \frac{3}{4} - 1\frac{1}{3}\\x - \frac{2}{3} = \frac{3}{4} - \frac{4}{3}\\x - \frac{2}{3} = \frac{9}{{12}} - \frac{{16}}{{12}}\\x - \frac{2}{3} = \frac{{ - 7}}{{12}}\\x = \frac{{ - 7}}{{12}} + \frac{2}{3}\\x = \frac{{ - 7}}{{12}} + \frac{8}{{12}}\\x = \frac{1}{12}\end{array}\)

Vậy\(x = \frac{1}{12}\).

c)

\(\begin{array}{l}1\frac{1}{4}:\left( {x - \frac{2}{3}} \right) = 0,75\\\frac{5}{4}:\left( {x - \frac{2}{3}} \right) = \frac{3}{4}\\x - \frac{2}{3} = \frac{5}{4}:\frac{3}{4}\\x - \frac{2}{3} = \frac{5}{4}.\frac{4}{3}\\x - \frac{2}{3} = \frac{5}{3}\\x = \frac{5}{3} + \frac{2}{3}\\x = \frac{7}{3}\end{array}\)               

Vậy \(x = \frac{7}{3}\).

d)

\(\begin{array}{l}\left( { - \frac{5}{6}x + \frac{5}{4}} \right):\frac{3}{2} = \frac{4}{3}\\ - \frac{5}{6}x + \frac{5}{4} = \frac{4}{3}.\frac{3}{2}\\ - \frac{5}{6}x + \frac{5}{4} = 2\\ - \frac{5}{6}x = 2 - \frac{5}{4}\\ - \frac{5}{6}x = \frac{8}{4} - \frac{5}{4}\\ - \frac{5}{6}x = \frac{3}{4}\\x = \frac{3}{4}:\left( { - \frac{5}{6}} \right)\\x = \frac{3}{4}.\frac{{ - 6}}{5}\\x = \frac{{ - 9}}{{10}}\end{array}\)

Vậy \(x = \frac{{ - 9}}{{10}}\).

\(\frac{-11}{9}\le x+\frac{11}{18}\Leftrightarrow x\ge\frac{-11}{6}\)

\(-4\frac{1}{3}.\left(\frac{1}{2}-\frac{1}{6}\right)\le x-\frac{2}{3}.\left(\frac{1}{3}-\frac{1}{2}-\frac{3}{4}\right)\)

\(\Rightarrow\frac{-13}{9}\le x-\frac{-11}{18}\)

\(\Leftrightarrow\frac{-13}{9}\le x+\frac{11}{18}\)

\(\Rightarrow x\ge\frac{-37}{18}\)

Học tốt nhé !! ^-^

cảm ơn Lâm Việt Phúc nhé