Question

Решите систему уравнений способом сложения x + y = 0, y - x = -2.

Answer 1

x + y = 0 | x + x-2 = 0 | 2x = 2 | x = 1

y - x = -2 | y = x-2 | y = x-2 | y = 1-2 = -1

x = 1, y = -1