Question

Решите систему уравнений способом сложения:
2x-3y=-13
x-y=-7​

Answer 1

Ответ:

$2x - 3y = - 13 \\ x - y = - 7 \\ 2x - 3y = - 13 \\ x = 7 - y \\ 2 \times (7 - y) - 3y = - 13 \\ 14 - 2y - 3y = - 13 \\ 14 - 5y = - 13 \\ - 5y = - 13 - 14 \\ - 5y = - 27 \\ y = 5.4 \\ \\ x = 7 - 5.4 \\ x = 1.6$