Question

2x+y=-1 x+2y=1 pfvrrrrrr

Answer 1

Resposta:

2x + y = -1

x + 2y = 1

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3x + 3y = 0

3x = -3y

x = -3y/3

× = - y

2x + y = -1

2 (-y) + y = -1

-2y + y = -1

y = -1