$\frac{17}{20} - x = \frac{14}{20} - \frac{3}{20}$
$x = \frac{17}{20} - \frac{11}{20}$
$x = \frac{6}{20}$

$\frac{8}{15} - \frac{7}{15} + y = \frac{14}{15}$
$y = \frac{14}{15} - \frac{1}{15}$
$y = \frac{13}{15}$