\(\frac{1}{3}-\frac{2}{5}.\left(x+1\right)=0\)
\(\frac{2}{5}.\left(x+1\right)=\frac{1}{3}-0\)
\(\frac{2}{5}.\left(x+1\right)=\frac{1}{3}\)
\(x+1=\frac{1}{3}:\frac{2}{5}\)\(x+1=\frac{5}{6}\)
\(x=\frac{5}{6}-1\)
\(x=\frac{-1}{6}\)
Vậy x = \(\frac{-1}{6}\)