\[\boxed{\mathbf{2}\mathbf{.}\mathbf{212}}\]
\[\textbf{а)}\ (x - 47) + 63 = 100\]
\[x - 47 = 100 - 63\]
\[x - 47 = 37\]
\[x = 37 + 47\]
\[x = 84.\ \]
\[\textbf{б)}\ 120 - (x + 96) = 24\]
\[x + 96 = 120 - 24\]
\[x + 96 = 96\]
\[x = 96 - 96\]
\[x = 0.\]
\[\textbf{в)}\ 48 + (56 - x) = 48\]
\[56 - x = 48 - 48\]
\[56 - x = 0\]
\[x = 56 - 0\]
\[x = 56.\]
\[\textbf{г)}\ (90 - x) - 42 = 58\]
\[90 - x = 58 + 42\]
\[90 - x = 100\]
\[x = 90 - 100\]
\[90 < 100\]
\[нет\ корней.\ \]