\(\left(\frac{5}{7}-y\right)\times\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)
\(\left(\frac{5}{7}-y\right)\times\frac{14}{5}=\frac{6}{5}\)
\(\frac{5}{7}-y=\frac{6}{5}:\frac{14}{5}\)
\(\frac{5}{7}-y=\frac{3}{7}\)
\(y=\frac{5}{7}-\frac{3}{7}\)
\(y=\frac{2}{7}\)