Bài 1 : 

\(=\dfrac{2}{11}+\dfrac{4}{11}-\dfrac{6}{11}-\dfrac{3}{8}-\dfrac{5}{8}=0-1=-1\)

Bài 2 : 

\(\Rightarrow3+x=8\Leftrightarrow x=5\)

Bài 3 : 

\(\Leftrightarrow x-\dfrac{5}{11}=\dfrac{5}{4}\Leftrightarrow x=\dfrac{35}{44}\)

Bài 4 : 

Trong 2 ngày An đọc được số quyên phần quyên sách 

\(\dfrac{1}{11}+\dfrac{8}{11}=\dfrac{9}{11}\)( quyển sách ) 

đs : 9/11 quyển sách 

a) \(x-\dfrac{5}{6}=\dfrac{1}{2}\)

           \(x=\dfrac{1}{2}+\dfrac{5}{6}\)

           \(x=\dfrac{4}{3}\)

vậy x = ....

b) \(3\dfrac{1}{3}x+16\dfrac{3}{4}=-13,25\)

    \(\dfrac{10}{3}\)\(x+\dfrac{67}{4}=-13,25\)

     \(\dfrac{10}{3}x=\left(-13,25\right)-\dfrac{67}{4}\)

      \(\dfrac{10}{3}x=-30\)

          \(x=\left(-30\right):\dfrac{10}{3}\)

         \(x=-9\)

vậy x =...

sai mog bn thông cảm!!!

Cộng hai vế với 1

\(\Rightarrow\dfrac{x+1}{9}+\dfrac{x+4}{6}+\dfrac{x+5}{5}+3=\dfrac{x+2}{8}+\dfrac{x+3}{7}+\dfrac{x+6}{4}+3\)

\(\Rightarrow\left(\dfrac{x+1}{9}+1\right)+\left(\dfrac{x+4}{6}+1\right)+\left(\dfrac{x+5}{5}+1\right)=\left(\dfrac{x+2}{8}+1\right)+\left(\dfrac{x+3}{7}+1\right)+\left(\dfrac{x+6}{4}+1\right)\)\(\Rightarrow\left(\dfrac{x+1}{9}+\dfrac{9}{9}\right)+\left(\dfrac{x+4}{6}+\dfrac{6}{6}\right)+\left(\dfrac{x+5}{5}+\dfrac{5}{5}\right)=\left(\dfrac{x+2}{8}+\dfrac{8}{8}\right)+\left(\dfrac{x+3}{7}+\dfrac{7}{7}\right)+\left(\dfrac{x+6}{4}+\dfrac{4}{4}\right)\)\(\Rightarrow\dfrac{x+10}{9}+\dfrac{x+10}{6}+\dfrac{x+10}{5}=\dfrac{x+10}{8}+\dfrac{x+10}{7}+\dfrac{x+10}{4}\)

\(\Rightarrow\dfrac{x+10}{9}+\dfrac{x+10}{6}+\dfrac{x+10}{5}-\dfrac{x+10}{8}-\dfrac{x+10}{7}-\dfrac{x+10}{4}=0\)

\(\Rightarrow\left(x+10\right)\left(\dfrac{1}{9}+\dfrac{1}{6}+\dfrac{1}{5}-\dfrac{1}{8}-\dfrac{1}{7}-\dfrac{1}{4}\right)=0\)

Làm nốt đi, tính như bình thường

nhanh đi nhé

KHO QUÁ ĐI

a) x + 2/5 = -4/3

x = -4/3 - 2/5

x = -26/15

b) -5/6 + 1/3 x = (-1/2)²

-5/6 + 1/3 x = 1/4

1/3 x = 1/4 + 5/6

1/3 x = 13/12

x = 13/12 : 1/3

x = 13/4

c) 7/12 - (x + 7/6) . 6/5 = (-1/2)³

7/12 - (x + 7/6) . 6/5 = -1/8

(x + 7/6) . 6/5 = 7/12 + 1/8

(x + 7/6) . 6/5 = 17/24

x + 7/6 = 17/24 : 6/5

x + 7/6 = 85/144

x = 85/144 - 7/6

x = -83/144

\(a,x+\dfrac{2}{5}=-\dfrac{4}{3}\\ \Rightarrow x=-\dfrac{26}{15}\\ b,-\dfrac{5}{6}+\dfrac{1}{3}x=\left(-\dfrac{1}{2}\right)^2\\ \Rightarrow-\dfrac{5}{6}+\dfrac{1}{3}x=\dfrac{1}{4}\\ \Rightarrow\dfrac{1}{3}x=\dfrac{13}{12}\\ \Rightarrow x=\dfrac{13}{4}\\ c,\dfrac{7}{12}-\left(x+\dfrac{7}{6}\right).\dfrac{6}{5}=\left(-\dfrac{1}{2}\right)^3\\ \Rightarrow\dfrac{7}{12}-\left(x+\dfrac{7}{6}\right).\dfrac{6}{5}=-\dfrac{1}{8}\\ \Rightarrow\left(x+\dfrac{7}{6}\right).\dfrac{6}{5}=\dfrac{17}{24}\\ \Rightarrow x+\dfrac{7}{6}=\dfrac{85}{144}\\ \Rightarrow x=-\dfrac{83}{144}.\)

a) x= -26/15

b) x= 17/12

c) x= -1/3

a) \(\dfrac{1}{2}-\left(x+\dfrac{1}{3}\right)=\dfrac{5}{6}\)

\(\Rightarrow x+\dfrac{1}{3}=\dfrac{1}{2}-\dfrac{5}{6}\)

\(\Rightarrow x+\dfrac{1}{3}=\dfrac{3}{6}-\dfrac{5}{6}\)

\(\Rightarrow x+\dfrac{1}{3}=-\dfrac{2}{6}\)

\(\Rightarrow x=-\dfrac{2}{6}-\dfrac{1}{3}\)

\(\Rightarrow x=-\dfrac{2}{3}\)

b) \(\left(\dfrac{3}{8}-\dfrac{1}{5}\right)+\left(\dfrac{5}{8}-x\right)=\dfrac{1}{5}\)

\(\Rightarrow\left(\dfrac{15}{40}-\dfrac{8}{40}\right)+\left(\dfrac{5}{8}-x\right)=\dfrac{1}{5}\)

\(\Rightarrow\dfrac{7}{40}+\left(\dfrac{5}{8}-x\right)=\dfrac{1}{5}\)

\(\Rightarrow\dfrac{5}{8}-x=\dfrac{1}{5}-\dfrac{7}{40}\)

\(\Rightarrow\dfrac{5}{8}-x=\dfrac{1}{40}\)

\(\Rightarrow x=\dfrac{5}{8}-\dfrac{1}{40}\)

\(\Rightarrow x=\dfrac{3}{5}\)

x+13=12−56x+13=12−56

x=−13−13x=−13−13

x=−23x=−23;
b) 

a) x= -2/3

b) x=3/5

\(x:\left(3\dfrac{1}{2}-5\dfrac{1}{6}\right)=4\dfrac{1}{5}-6\dfrac{2}{3}\)

<=>\(x:\dfrac{2}{3}=\dfrac{-37}{15}\)

<=>\(\dfrac{-37}{15}\cdot\dfrac{2}{3}\)

<=>\(\dfrac{-74}{45}\)

x=-1

ve trai = -1/10con ve phai=-36/35

a) \(\dfrac{1}{2}x-\dfrac{3}{4}x-\dfrac{7}{3}=-\dfrac{5}{6}\\ < =>-\dfrac{1}{4}x-\dfrac{7}{3}=-\dfrac{5}{6}\\ < =>-\dfrac{1}{4}x=-\dfrac{5}{6}+\dfrac{7}{3}=\dfrac{3}{2}\\ =>x=\dfrac{3}{2}:\dfrac{-1}{4}=-6\)

b) \(\left|x-\dfrac{1}{6}\right|+-\dfrac{5}{12}=\dfrac{4}{7}.\dfrac{14}{48}\\ < =>\left|x-\dfrac{1}{6}\right|=\left(\dfrac{4}{7}.\dfrac{14}{48}\right)-\left(-\dfrac{5}{12}\right)=\dfrac{1}{6}+\dfrac{5}{12}=\dfrac{7}{12}\\ \)

Xảy ra 2 trường hợp:

+) TH1: \(x-\dfrac{1}{6}=\dfrac{7}{12}\\ =>x=\dfrac{7}{12}+\dfrac{1}{6}=\dfrac{3}{4}->\left(a\right)\)

+) TH2" \(-\left(x-\dfrac{1}{6}\right)=\dfrac{7}{12}\\ < =>-x+\dfrac{1}{6}=\dfrac{7}{12}\\ < =>-x=\dfrac{7}{12}-\dfrac{1}{6}=\dfrac{5}{12}\\ =>x=-\dfrac{5}{12}->\left(b\right)\)

Từ (a) và (b) => \(x\in\left\{-\dfrac{5}{12};\dfrac{3}{4}\right\}\)

a, \(\dfrac{1}{2}x-\dfrac{3}{4}x-\dfrac{7}{3}=\dfrac{-5}{6}\)

\(\Rightarrow\dfrac{-1}{4}x=\dfrac{-5}{6}+\dfrac{7}{3}\)

\(\Rightarrow\dfrac{-1}{4}x=\dfrac{3}{2}\Rightarrow x=-6\)

Vậy \(x=-6\)

b, \(\left|x-\dfrac{1}{6}\right|+\dfrac{-5}{12}=\dfrac{4}{7}.\dfrac{14}{48}\)

\(\Rightarrow\left|x-\dfrac{1}{6}\right|-\dfrac{5}{12}=\dfrac{1}{6}\)

\(\Rightarrow\left|x-\dfrac{1}{6}\right|=\dfrac{7}{12}\)

\(\Rightarrow\left\{{}\begin{matrix}x-\dfrac{1}{6}=\dfrac{-7}{12}\\x-\dfrac{1}{6}=\dfrac{7}{12}\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=\dfrac{-5}{12}\\x=\dfrac{3}{4}\end{matrix}\right.\)

Vậy \(x\in\left\{\dfrac{-5}{12};\dfrac{3}{4}\right\}\)

Chúc bạn học tốt!!!

\(a,\dfrac{1}{2}x-\dfrac{3}{4}x-\dfrac{7}{3}=-\dfrac{5}{6}\\ \dfrac{1}{2}x-\dfrac{3}{4}x=\dfrac{-5}{6}+\dfrac{7}{3}\\ x\left(\dfrac{1}{2}-\dfrac{3}{4}\right)=\dfrac{-5}{6}+\dfrac{14}{6}\\ x\left(\dfrac{2}{4}-\dfrac{3}{4}\right)=\dfrac{9}{6}\\ \dfrac{-1}{4}x=\dfrac{3}{2}\\ x=\dfrac{3}{2}:\dfrac{-1}{4}\\ x=\dfrac{3}{2}\cdot\left(-4\right)\\ x=-6\)