Question

Помогите!
Даю 40 балов

Answer 1

3)

$8(2 - y) = - 3(1 + 2y) \\ 16 - 8y = - 3 - 6y \\ - 6y + 8y = 16 + 3 \\ 2y = 19 \\ y = 19 \div 2 \\ y = 9.5$

4)

$(a - 3)x = 3 + 4a \\ x _{1} = 5 \\ 5(a - 3) = 3 + 4a \\ 5a - 15 = 3 + 4a \\ 5a - 4a = 3 + 15 \\ a = 18$