Question

Решите системы уравнений способом подстановки: #1427(1) ​

Answer 1

$2(x + y) - x + 6 = 0 \\ 3x - (x - y) = 0 \\ \\ 2x + 2y - x + 6 = 0 \\ 3x - x + y = 0 \\ \\ x + 2y + 6 = 0 \\ 2x + y = 0 \\ \\ x + 2 \times ( - 2x) + 6 = 0 \\ y = - 2x \\ \\ x + 2 \times ( - 2x) + 6 = 0 \\ x - 4x + 6 = 0 \\ - 3x = - 6 \\ x = - 6 \div ( - 3) \\ x = 2 \\ \\ y = - 2x = - 2 \times 2 = - 4$

Ответ: (2 ; -4)