Question

плиз помогите решить..я плохо понимаю алгебру :(​

Answer 1

Задание 2

$\frac{1}{8} a + 1 \frac{2}{16} (a - 8b + 1 \frac{7}{9} ) + 9b - 1 \frac{2}{8} a - 3 = \frac{1}{8} a + 1 \frac{1}{8} (a - 8b + \frac{16}{9} ) + 9b - 1 \frac{1}{4} a - 3 = \frac{1}{8} a + \frac{9}{8} a - 9b + 2 + 9b - \frac{5}{4} a - 3 = \frac{10}{8} a + 2 - 3 - \frac{5}{4} a = \frac{5}{4} a - \frac{5}{4} a - 1 = - 1$

Задание 3

$\frac{6}{7} (1.4a - 2 \frac{1}{3} b) - \frac{1}{2} (0.4a - 2b) = \frac{6}{7} (1 \frac{4}{10} a - \frac{7}{3} b) - \frac{1}{2} ( \frac{4}{10} a - 2b) = \frac{6}{7} ( \frac{7}{5} a - \frac{7}{3} b) - \frac{1}{2} ( \frac{2}{5} a - 2b) = \frac{6}{5} a - 2b - \frac{1}{5} a + b = a - b$

$- \frac{3}{8} - 0.25 = - \frac{3}{8} - \frac{25}{100} = - \frac{3}{8} - \frac{1}{4} = - \frac{3 + 2}{8} = - \frac{5}{8}$