How do you solve the system of equations $-x - y = 12$ and $3x - y = - 12$ ?

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Answer 1 · 2018-04-12T03:26:54

$x=-6=>y=-6$

You can use the substitution method for this one.

Let’s call,
$-x-y=12$ equation $(1)$ and
$3x-y=-12$ equation $(2)$

From $(1)$ : $-y=x+12$

Now, substitute $-y=x+12$ into $(2)$ ,

$3x+(x+12)=-12$

$4x=-24$

$x=-6=>y=-6$ by substituting $x=-6$ back into equation $(1)$ or $(2)$

How do you solve the system of equations -x - y = 12-x - y = 12 and 3x - y = - 123x - y = - 12?