How do you solve the following system: $- 5 x - y = 14, y + 4 x = 16$ $-5x − y = 14 , y + 4x = 16$ ?

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Answer 1 · 2018-04-17T00:04:00

$x = - 30, y = 136$ $x=-30, y=136$

You have to substitute the $y$ $y$ in one equation for the one in the other equation:

$- 5 x - y = 14$ $-5x-y=14$

$y + 4 x = 16 \Rightarrow y = - 4 x + 16$ $y+4x=16 =>y=-4x+16$

So

$- 5 x - (- 4 x + 16) = 14$ $-5x-(-4x+16)=14$

$- 1 x - 16 = 14$ $-1x-16=14$

$- 1 x = 30$ $-1x=30$

$x = - 30$ $x=-30$

Now you can plug in the $x$ $x$ you found to either equation to find the $y$ $y$ .

$- 5 (- 30) - y = 14$ $-5(-30)-y=14$

$150 - y = 14$ $150-y=14$

$y = 136$ $y=136$

How do you solve the following system: −5x−y=14,y+4x=16-5x − y = 14 , y + 4x = 16 ?