Ответ:

а)

\(x = 23\frac{2}{17} - 12\frac{3}{17} - 8\frac{16}{17}\)

\(x = \frac{393}{17} - \frac{207}{17} - \frac{152}{17} = \frac{34}{17} = 2\).

б)

\(5.9x - 5.21 = 9.54\)

\(5.9x = 9.54 + 5.21 = 14.75\)

\(x = 14.75 : 5.9 = 2.5\).

Ответ: а) \(x = 2\); б) \(x = 2.5\).