\[\boxed{\mathbf{92}.}\]
\[1)\ 2x - 8 = 6\]
\[2x = 6 + 8\]
\[2x = 14\]
\[x = 7.\]
\[Ответ:число\ 7.\]
\[2)\ 20 - 84\ :x = 13\]
\[84\ :x = 20 - 13\]
\[84\ :x = 7\]
\[x = 84\ :7\]
\[x = 12.\]
\[Ответ:число\ 12.\]