\(2.\left(x+\frac{3}{5}\right)=5-\left(\frac{13}{5}+x\right)\)

<=>\(2x+\frac{6}{5}=5-\frac{13}{5}+x\)

<=> \(2x+\frac{6}{5}=\frac{12}{5}+x\)

<=>\(2x-x=\frac{12}{5}-\frac{6}{5}\)

<=>x=\(\frac{6}{5}\)

Vậy S=\(\left\{\frac{6}{5}\right\}\)