Question

\(1\dfrac{2}{5}x+\dfrac{3}{7}=\dfrac{-4}{5}\)

Answer 1

\(1\dfrac{2}{5}x+\dfrac{3}{7}=\dfrac{-4}{5}\)

\(\Rightarrow1\dfrac{2}{5}x=\dfrac{-4}{5}-\dfrac{3}{7}\)

\(\Rightarrow1\dfrac{2}{5}x=\dfrac{-43}{35}\)

\(\Rightarrow x=\dfrac{-43}{35}:1\dfrac{2}{5}\)

\(\Rightarrow\dfrac{-43}{49}\)

Vậy.............

Answer 2

\(1\dfrac{2}{5}x+\dfrac{3}{7}=\dfrac{-4}{5}\)

\(\Leftrightarrow\dfrac{7}{5}x+\dfrac{3}{7}=\dfrac{-4}{5}\)

\(\Leftrightarrow\dfrac{7}{5}x=\dfrac{-4}{5}-\dfrac{3}{7}=\dfrac{-43}{35}\)

\(\Leftrightarrow x=\dfrac{-43}{35}.\dfrac{5}{7}=\dfrac{-43}{49}\)