a) \(y+\frac{3}{4}=\frac{4}{5}\)

\(y=\frac{4}{5}-\frac{3}{4}\)

\(y=\frac{1}{20}\)

b) \(y-\frac{3}{11}=\frac{9}{22}\)

\(y=\frac{9}{22}-\frac{3}{11}\)

\(y=\frac{3}{22}\)

c) \(\frac{9}{2}-y=\frac{2}{9}\)

\(y=\frac{9}{2}-\frac{2}{9}\)

\(y=\frac{77}{18}\)

a, y + 3/4 = 4/5

            y = 4/5 - 3/4

             y = 1/20

b, y - 3/11 = 9/22

              y = 9/22 + 3/11

              y = 15/22

c, 9/2 - y = 2/9

           y = 9/2 - 2/9

            y = 77/18

ủng hộ nha

\(y-\frac{3}{11}=\frac{9}{22}\)

\(y=\frac{9}{22}+\frac{3}{11}\)

\(y=\frac{9}{22}+\frac{6}{22}\)

\(y=\frac{9+6}{22}\)

\(y=\frac{15}{22}\)

\(y+\frac{3}{4}=\frac{4}{5}\)

          \(y=\frac{4}{5}-\frac{3}{4}\)

         \(y=\frac{1}{20}\)

Vậy y = 1/20

\(y-\frac{3}{11}=\frac{9}{22}\)

          \(y=\frac{9}{22}+\frac{3}{11}\)

          \(y=\frac{15}{22}\)

Vậy y = 15/22

\(\frac{9}{2}-y=\frac{2}{9}\)

         \(y=\frac{9}{2}-\frac{2}{9}\)

        \(y=\frac{77}{18}\)

Vậy y = 77/18

Cảm ơn Sakura!

a) y = 4/5-3/4 = 1/20 

b) y = 9/22 + 3/11 =15/22

c)y = 9/2 - 2/9 = 77/18

a)1/20 , b)15/22, c)77/18

77/18

a) \(\frac{7}{11}-\left(\frac{3}{5}+\frac{7}{11}\right)=-\frac{3}{5}\)

b) \(\left(\frac{11}{22}+\frac{5}{11}\right)-\frac{19}{22}=\frac{1}{11}\)

c) \(\frac{2}{9}.\frac{4}{5}+\frac{2}{9}.\frac{14}{5}=\frac{4}{5}\)

d) \(-\frac{3}{2}.\frac{7}{10}-\frac{3}{2}.\frac{1}{10}=-\frac{6}{5}\)

e) \(\left(0,75-1+\frac{1}{4}\right):\left(\frac{1515}{1616}+\frac{1616}{1717}\right)=0\)

mn. giúp em nha 

\(a.\dfrac{6}{5}=\dfrac{18}{x}\Rightarrow x=\dfrac{18\cdot5}{6}=15\\ \text{Vậy}\text{ }x=15.\)

\(b.\dfrac{3}{4}=\dfrac{-21}{x}\Rightarrow x=\dfrac{-21\cdot4}{3}=28\\ \text{ }\text{ }\text{ }\text{ }\text{Vậy }x=28.\)

\(c.\dfrac{x}{4}=\dfrac{21}{28}\Rightarrow x=\dfrac{21\cdot4}{28}=3\\ \text{Vậy }x=3.\)

\(d.\dfrac{-8}{2x}=\dfrac{3}{-9}\Rightarrow x=\dfrac{-8\cdot\left(-9\right)}{3}:2=12\\ \text{Vậy }x=12.\)

\(e.\dfrac{-4}{11}=\dfrac{x}{22}=\dfrac{40}{z}\\ \Rightarrow x=\dfrac{-4\cdot22}{11}=-8\\ \Rightarrow z=\dfrac{22\cdot40}{-8}=-110\\ \text{Vậy }x=-8;z=-110.\)

\(f.\dfrac{-3}{4}=\dfrac{x}{20}=\dfrac{21}{y}\\ \Rightarrow x=\dfrac{-3\cdot20}{4}=-15\\ \Rightarrow y=\dfrac{21\cdot20}{-15}=-28\\ \text{Vậy }x=-15;y=-28.\)

\(g.\dfrac{-4}{8}=\dfrac{x}{-10}=\dfrac{-7}{y}=\dfrac{z}{-24}\\ \Rightarrow x=\dfrac{-4\cdot\left(-10\right)}{8}=5\\ \Rightarrow y=\dfrac{-7\cdot\left(-10\right)}{5}=14\\ \Rightarrow z=\dfrac{-7\cdot\left(-24\right)}{14}=12\\ \text{Vậy }x=5;y=14;z=12.\)

\(h.\dfrac{x}{4}=\dfrac{9}{x}\\ \Rightarrow x\cdot x=9\cdot4\\ \Rightarrow x\cdot x=36\\ \Rightarrow x\cdot x=6\cdot6\\ \text{Vậy }\text{cả hai }x=6.\)

<=> x = 9/22 + 3/11 = 9/22 + 6/22 = 15/22 

x-3/11=9/22

       x =9/22+6/22

        x=15/22

x = 9/22 + 3/11 = 9/22 + 6/22 = 15/22