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How do you solve x = y - 8 & -x - y = 0?

1 Answer

José Roberto Pereira

Oct 18, 2015

$x = - 4$ $x=-4$
$y = 4$ $y=4$

Explanation:

$y = x + 8$ $y=x+8$ (1)
$y = - x$ $y=-x$ (2)

Subtracting (1) - (2):

$0 = 2 x + 8$ $0=2x+8$

$2 x = - 8$ $2x=-8$

$x = - \frac{8}{2} = - 4$ $x=-8/2=-4$

$y = - (- 4) = 4$ $y=-(-4) =4$

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