How do you solve the following system?: $-x -6y =-1, 3x -y = -4$

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Answer 1 · 2015-11-17T21:52:01

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Isolate one variable in one the equations. Then use the resulting equivalent to replace the same variable in the other equation

$-x - 6y = -1$
$3x - y = -4$

If we isolate $x$ in the first equation, we will have

$-x - 6y = -1$
$=> x = -6y + 1$

Now, let's replace $x$ in the second equation

$3x - y = -4$
$=> 3(-6y + 1) - y = -4$
$=> -18y + 3 - y = -4$
$=> -19y + 3 = -4$
$=> -19y = -7$
$=> y = 7/19$

Now that we have the value for $y$ , substitute it into any of the equalities above to get $x$

$x = -6y + 1$
$=> x = -6(7/19) + 1$
$=> x = -42/19 + 1$

$=> x = (-42 + 19)/19$

$=> x = -23/19$

How do you solve the following system?: -x -6y =-1, 3x -y = -4-x -6y =-1, 3x -y = -4