Помогите решить все задания срочно нужно

1)
$- 2(8a + 7b) + 4(a - 2b) = - 16a - 14b + 4a - 8b = - 12a - 22b$
2)
$5(2x - 3) - 2(3 - 2x) = 15 - 6(x + 1) \\ 10x - 15 - 6 + 4x = 15 - 6x - 6 \\ 10x + 4x + 6x = 15 - 6 + 15 + 6 \\ 20 x = 30 \\ x = 30 \div 20 \\ x = 1 \times \frac{1}{2}$
4)
$\frac{19}{12} + \frac{41}{7} \div ( \frac{12}{5} - \frac{25}{7}) = \frac{19}{12} + \frac{41}{7} \div ( \frac{84}{35} - \frac{125}{35}) = \frac{19}{12} + \frac{41}{7} \div ( - \frac{41}{35} ) = \frac{19}{12} - \frac{41}{7} \times \frac{35}{41 } = \frac{19}{12} - 5 = - \frac{41}{12} = - 3 \frac{5}{12}$
3 и 5 задание я не знаю