Question

[Tung Duong]

Tìm x biết :

a , \(\frac{2}{3}\cdot x-\frac{4}{7}=\frac{1}{8}\)

b , \(\frac{2}{7}-\frac{8}{9}\cdot x=\frac{2}{3}\)

c , \(\frac{4}{7}+\frac{5}{4}:x=\frac{1}{5}\)

d , \(\frac{2}{3}-\frac{2}{5}\cdot x=\frac{2}{5}\)

Help me !!!

Ai nhanh + đúng cho 3 tik !!!!

Answer 1

[Huỳnh Quang Sang]

\(a,\frac{2}{3}\cdot x-\frac{4}{7}=\frac{1}{8}\)

\(\Leftrightarrow\frac{2}{3}\cdot x=\frac{1}{8}+\frac{4}{7}\)

\(\Leftrightarrow\frac{2}{3}\cdot x=\frac{7}{56}+\frac{32}{56}\)

\(\Leftrightarrow\frac{2}{3}\cdot x=\frac{39}{56}\)

\(\Leftrightarrow x=\frac{39}{56}:\frac{2}{3}=\frac{39}{56}\cdot\frac{3}{2}=\frac{39\cdot3}{56\cdot2}=\frac{117}{112}\)

\(b,\frac{2}{7}-\frac{8}{9}\cdot x=\frac{2}{3}\)

\(\Leftrightarrow\frac{8}{9}\cdot x=\frac{2}{7}-\frac{2}{3}\)

\(\Leftrightarrow\frac{8}{9}\cdot x=\frac{6}{21}-\frac{14}{21}\)

\(\Leftrightarrow\frac{8}{9}\cdot x=\frac{-8}{21}\)

\(\Leftrightarrow x=\frac{-8}{21}:\frac{8}{9}=\frac{-8}{21}\cdot\frac{9}{8}=\frac{-8\cdot9}{21\cdot8}=\frac{-1\cdot3}{7\cdot1}=\frac{-3}{7}\)

Làm nốt hai bài cuối đi nhé

Study well >_<

Answer 2

[#Tiểu_Tỷ_Tỷ⁀ᶜᵘᵗᵉ]

Mk k chép lại đề bài nha

a)\(\frac{2}{3}.x=\frac{1}{8}+\frac{4}{7}\)

   \(\frac{2}{3}.x=\frac{7}{56}+\frac{32}{56}\)

    \(\frac{2}{3}.x=\frac{39}{56}\)

     \(x=\frac{39}{56}:\frac{2}{3}\)

     \(x=\frac{39}{56}.\frac{3}{2}\)

     \(x=\frac{117}{112}\)

Mk sợ sai lém!!!