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How do you solve y= 4x + 45 and x= 4y?

1 Answer

Oct 4, 2015

$x=-12$ , $y=-3$

Explanation:

Knowing that $x=4y$ , you can write the first equation as

$y=4(4y)+45 -> y=16y+45 -> -15y=45$ , isolating the $y$ -terms by bringing them all to the left. Now, solving by $y$ , we have $y=-3$ .

Since $x$ was $4y$ , we know that $x=4*(-3)$ , and thus $x=-12$ and the system is solved.

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