Question

Решите систему 3x-y=x+8
2x+y=5-x-y

Answer 1

$3x - y = x + 8 \ 2x + y = 5 - x - y \ \ 3x - x - y = 8 \ 2x + x + y + y = 5 \ \ 2x - y = 8 \ 3x + 2y = 5 \ \ 4x - 2y = 16 \ 3x + 2y = 5 \ \ 7x = 21 \ y = 2x - 8 \ \ x = 3 \ y = 2 times 3 - 8 = - 2$
Ответ: (3; -2)