\[\boxed{\mathbf{17\ (15)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[18 < x < 36\ \ \ \ \ \ \ \]
\[x = 20,\ 24,\ 28,\ 32.\ \]
\[\boxed{\mathbf{17\ (}\mathbf{с}\mathbf{)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[7 < x < 40\ \ \ \ \ \ \]
\[x = 8,\ 10,\ 16,\ 20.\]