a) \(\frac{x}{3}=\frac{1}{5}-\frac{1}{3}\) =>\(\frac{x}{3}=\frac{3}{15}-\frac{5}{15}\)=>\(\frac{x}{3}=\frac{2}{15}\)=>\(x=\frac{2.3}{15}=\frac{2}{5}\)
b) \(\frac{-2}{7}-\frac{1}{3}=\frac{7}{x}\) =>\(\frac{-6}{21}-\frac{7}{21}=\frac{7}{x}\) =>\(\frac{-13}{21}=\frac{7}{x}\)=>\(x=\frac{-13.7}{21}=\frac{-13}{3}\)
Nhớ k cho mik nha (^o^)