\[ \frac{8(5y+8)}{56} - \frac{7(3y-1)}{56} = 5 \]
\[ \frac{40y + 64 - (21y - 7)}{56} = 5 \]
\[ \frac{40y + 64 - 21y + 7}{56} = 5 \]
\[ \frac{19y + 71}{56} = 5 \]
\[ 19y + 71 = 5 \times 56 \]
\[ 19y + 71 = 280 \]
\[ 19y = 280 - 71 \]
\[ 19y = 209 \]
\[ y = \frac{209}{19} \]
\[ y = 11 \]
Ответ: 11