a) $x$ + $\frac{3}{5}$ = $\frac{7}{2}$
$x$ = $\frac{7}{2}$ - $\frac{3}{5}$
$x$ = $\frac{35}{10}$ - $\frac{6}{10}$
$x$ = $\frac{29}{10}$
b) $x$ - $\frac{1}{4}$ = $\frac{1}{5}$
$x$ = $\frac{1}{5}$ + $\frac{1}{4}$
$x$ = $\frac{4}{20}$ + $\frac{5}{20}$
$x$ = $\frac{9}{20}$
c) 2 - $x$ = $\frac{4}{7}$
$x$ = 2 - $\frac{4}{7}$
$x$ = $\frac{14}{7}$ - $\frac{4}{7}$
$x$ = $\frac{10}{7}$