Ta có: \(\frac{7}{8}-\frac{1}{3}x=\frac{7}{10}+\frac{2}{3}x\)

<=> \(\frac{7}{8}-\frac{7}{10}=\frac{2}{3}x+\frac{1}{3}x\)

<=>\(\frac{7}{40}=x\)

Vậy x=7/40

\(\frac{7}{8}-\frac{1}{3}x=\frac{7}{10}+\frac{2}{3}\)

\(\Leftrightarrow-\frac{1}{3}x-\frac{2}{3}x=\frac{7}{10}-\frac{7}{8}\)

\(\Leftrightarrow-x=-\frac{7}{40}\)

\(\Leftrightarrow x=\frac{7}{40}=0,175\)

Ta có: \(\frac{7}{8}-\frac{1}{3}.x=\frac{7}{10}+\frac{2}{3}.x\)

\(\Rightarrow\frac{7}{8}-\frac{7}{10}=\frac{2}{3}.x+\frac{1}{3}.x\)

\(\Rightarrow\frac{35}{40}-\frac{28}{40}=\left(\frac{2}{3}+\frac{1}{3}\right).x\)

\(\Rightarrow\frac{7}{40}=x\)

Vậy \(x=\frac{7}{40}\)

Chúc bạn hok tốt! 

Ta có: \(\frac{7}{10}-\frac{5}{8}.x-\frac{7}{6}=\frac{5}{6}.x\)

\(\Rightarrow\frac{7}{10}-\frac{7}{6}=\frac{5}{6}x+\frac{5}{8}x\)

\(\Rightarrow\frac{21}{30}-\frac{35}{30}=\left(\frac{5}{6}+\frac{5}{8}\right)x\)

\(\Rightarrow-\frac{7}{15}=\left(\frac{15}{24}+\frac{20}{24}\right)x\)

\(\Rightarrow-\frac{7}{15}=\frac{35}{24}x\)

\(\Rightarrow x=-\frac{7}{15}:\frac{35}{24}\)

\(\Rightarrow x=-\frac{7}{15}.\frac{24}{35}\)

\(\Rightarrow x=-\frac{8}{25}\)

Vậy \(x=-\frac{8}{25}\)

Chuk bạn hok tốt! 

Ta có:

\(\left(\right. \frac{13 \frac{2}{9} - 15 \frac{2}{3}}{18 \frac{3}{7} - 17 \frac{1}{4}} \cdot \frac{30^{2} - 5^{4}}{25 - 12 \cdot 5^{2}} \left.\right) \cdot x = \frac{\frac{2}{11} + \frac{3}{13} + \frac{4}{15} + \frac{5}{17}}{4 \frac{1}{11} + \frac{5}{13} + \frac{9}{15} + \frac{13}{17}}\)

Bước 1: Đổi hỗn số về phân số

Bước 2: Tính toán từng phần

Ta có:

\(\frac{119}{9} - \frac{47}{3} = \frac{119 - 141}{9} = \frac{- 22}{9}\) \(\frac{129}{7} - \frac{69}{4} = \frac{516 - 483}{28} = \frac{33}{28}\) \(30^{2} - 5^{4} = 900 - 625 = 275\) \(25 - 12 \cdot 25 = 25 - 300 = - 275\)

Khi đó:

\(\left(\right. \frac{- 22}{9} \div \frac{33}{28} \cdot \frac{275}{- 275} \left.\right) = \left(\right. \frac{- 22}{9} \cdot \frac{28}{33} \cdot \left(\right. - 1 \left.\right) \left.\right) = \frac{616}{297}\)

Bước 3: Tính vế phải

Tử số:

\(\frac{2}{11} + \frac{3}{13} + \frac{4}{15} + \frac{5}{17} = \frac{35494}{36465}\)

Mẫu số:

\(4 \frac{1}{11} + \frac{5}{13} + \frac{9}{15} + \frac{13}{17} = \frac{149645}{36465}\)

→ Vế phải:

\(\frac{35494}{36465} \div \frac{149645}{36465} = \frac{35494}{149645}\)

Bước 4: Giải phương trình

\(\frac{616}{297} \cdot x = \frac{35494}{149645} \Rightarrow x = \frac{35494}{149645} \cdot \frac{297}{616} = \frac{813}{7118}\)

Vậy:

\(\boxed{x = \frac{813}{7118}}\)

hỉu không =]]]

\(\text{GIẢI :}\)

ĐKXĐ : \(x\ne\pm1\)

\(\frac{2}{x+1}+\frac{x}{x-1}=\frac{\left[1\frac{1}{6}\cdot\frac{6}{7}+\left(\frac{1}{2}-\frac{1}{3}-\frac{1}{6}\right)\right]x+1}{x^2-1}\)

\(\Leftrightarrow\frac{2}{x+1}+\frac{x}{x-1}=\frac{x+1}{x^2-1}\)

\(\Leftrightarrow\frac{2}{x+1}+\frac{x}{x-1}-\frac{x+1}{x^2-1}=0\)

\(\Leftrightarrow\frac{2\left(x-1\right)}{\left(x+1\right)\left(x-1\right)}+\frac{x\left(x+1\right)}{\left(x+1\right)\left(x-1\right)}-\frac{x+1}{\left(x+1\right)\left(x-1\right)}=0\)

\(\Rightarrow\text{ }2\left(x-1\right)+x\left(x+1\right)-(x+1)=0\)

\(\Leftrightarrow\text{ }2\left(x-1\right)+\left(x+1\right)\left(x-1\right)=0\)

\(\Leftrightarrow\left(x-1\right)\left(2+x+1\right)=0\)

\(\Leftrightarrow\left(x-1\right)\left(x+3\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}x-1=0\\x+3=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x-1\text{ (loại)}\\x=-3\text{ (Chọn)}\end{cases}}}\)

Vậy tập nghiệm của phương trình là \(S=\left\{-3\right\}\).

\(\frac{2}{x+1}+\frac{x}{x-1}=\frac{\left[1\frac{1}{6}.\frac{6}{7}+\left(\frac{1}{2}-\frac{1}{3}-\frac{1}{6}\right)\right]x+1}{x^2-1}\)\(đk:x\ne\pm1\)

\(< =>\frac{2\left(x-1\right)}{\left(x-1\right)\left(x+1\right)}+\frac{x\left(x+1\right)}{\left(x+1\right)\left(x-1\right)}=\frac{\left[\frac{7}{6}.\frac{6}{7}+\left(1\right)\right]x+1}{x^2-1}\)

\(< =>\frac{2x-2+x^2+x}{x^2+x-x-1}=\frac{2x+1}{x^2-1}\)\(< =>\frac{x^2+3x-2}{x^2-1}=\frac{2x-1}{x^2-1}\)

\(< =>x^2+2x-2=2x-1\)\(< =>x^2+2x-2x-2+1=0\)

\(< =>x^2-1=0< =>x^2=1\)\(< =>x=\pm1\)\(\left(ktmđk\right)\)

Vậy phương trình trên vô nghiệm

a) 7x - 35 = 0

<=> 7x = 0 + 35

<=> 7x = 35

<=> x = 5

b) 4x - x - 18 = 0

<=> 3x - 18 = 0

<=> 3x = 0 + 18

<=> 3x = 18

<=> x = 5

c) x - 6 = 8 - x

<=> x - 6 + x = 8

<=> 2x - 6 = 8

<=> 2x = 8 + 6

<=> 2x = 14

<=> x = 7

d) 48 - 5x = 39 - 2x

<=> 48 - 5x + 2x = 39

<=> 48 - 3x = 39

<=> -3x = 39 - 48

<=> -3x = -9

<=> x = 3

có bị viết nhầm thì thông cảm nha!

la`thu'hai nga`y 19 nhe

a) A = \(\frac{19}{23}.\frac{-4}{27}-\frac{4}{23}.\frac{2}{7}\)

        = \(\frac{19}{7}.\frac{-4}{23}+\frac{-4}{23}.\frac{2}{7}\)

         = \(\frac{-4}{23}.\left(\frac{19}{7}+\frac{2}{7}\right)\) 

          = \(\frac{-4}{23}.3\)

          = \(\frac{-12}{23}\)

b) B = \(\frac{3}{5}+\frac{2}{5}.\frac{-11}{3}+\frac{2}{3}.\frac{-2}{5}+\frac{14}{15}\)

       = \(\frac{9+14}{15}+\frac{2}{5}.\frac{-11}{3}+\frac{-2}{3}.\frac{2}{5}\)

       = \(\frac{23}{15}+\frac{2}{5}\left(\frac{-11}{3}+\frac{-2}{3}\right)\)

       = \(\frac{23}{15}+\frac{2}{5}.\frac{-13}{3}\)

       = \(\frac{23}{15}+\frac{-26}{15}\)

       = \(\frac{-3}{15}=\frac{-1}{5}\)