\[\boxed{\mathbf{1099\ (1090)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ a - 8\]
\[- (a - 8) = 8 - a\]
\[2)\ a + 8\]
\[- (a + 8) = - a - 8\]
\[3) - a + 8\]
\[- ( - a + 8) = a - 8\]
\[4) - a - 8\]
\[- ( - a - 8) = a + 8\]