$\frac{3}{5}$$x$ + $\frac{1}{4}$ = $\frac{1}{3}$ - $\frac{1}{4}$$x$
$\frac{3x}{5}$ + $\frac{1}{4}$ = $\frac{1}{3}$ - $\frac{x}{4}$
$\frac{36x}{60}$ + $\frac{15}{60}$ = $\frac{20}{60}$ - $\frac{15x}{60}$
$36x$ + $15$ = $20$ - $15x$
$36x$ + $15x$ = $20$ - $15$
$51x$ = $5$
$x$ = $\frac{5}{51}$
Vậy $x$ = $\frac{5}{51}$
