б) 1 1/7 - 5/7 * n = 2/9

б) \(1 \frac{1}{7} - \frac{5}{7} n = \frac{2}{9}\) \(\frac{8}{7} - \frac{5}{7} n = \frac{2}{9}\) \(-\frac{5}{7} n = \frac{2}{9} - \frac{8}{7}\) \(-\frac{5}{7} n = \frac{14 - 72}{63}\) \(-\frac{5}{7} n = \frac{-58}{63}\) \(n = \frac{-58}{63} : (-\frac{5}{7})\) \(n = \frac{58}{63} \cdot \frac{7}{5}\) \(n = \frac{58 \cdot 7}{63 \cdot 5}\) \(n = \frac{406}{315}\) \(n = \frac{58}{45} = 1 \frac{13}{45}\)