Question

помогите решить второй пример.

Answer 1

$6 - 5(x - y) = 7x + 4y \\ 3(x + 1) - (6x + 8y) = 69 + 3y \\ \\ 6 - 5x + 5y = 7x + 4y \\ 3x + 3 - 6x - 8y = 69 + 3y \\ \\ - 5x - 7x + 5y - 4y = - 6 \\ 3x - 6x - 8y - 3y = 69 - 3 \\ \\ - 12x + y = - 6 \\ - 3x - 11y = 66 \\ \\ - 132x + 11y = - 66 \\ - 3x - 11y = 66 \\ \\ - 135x = 0 \\ y = 12x - 6 \\ \\ x = 0 \\ y = - 6$
Ответ: (0; -6)