How do you solve the system $x-4y=27$ and $3x+y=-23$ using substitution?

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Answer 1 · 2016-09-11T12:51:11

$x = - 5$ and $y = - 8$

We have: $x - 4 y = 27$ and $3 x + y = - 23$

Let's solve the first equation for $x$ :

$=> x = 27 + 4 y$

Now, let's substitute this expression for $x$ into the second equation:

$=> 3 (27 + 4 y) + y = - 23$

$=> 81 + 12 y + y = - 23$

$=> 13 y = - 104$

$=> y = - 8$

Now, let's substitute this value of $y$ into the expression for $x$ :

$=> x = 27 + 4 (- 8)$

$=> x = 27 - 32$

$=> x = - 5$

Therefore, the solutions to the system of equations are $x = - 5$ and $y = - 8$ .

How do you solve the system x-4y=27x-4y=27 and 3x+y=-233x+y=-23 using substitution?