How do you solve the following system?: $9x -5y =21, -x -y = -2$

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Answer 1 · 2018-06-27T02:21:50

$(31/14,-3/14)$

Let's start with the second equation by dividing every term by $-1$ . We now have the following system:

$color(blue)(9x-5y=21)$

$x+y=2$

Let's subtract $x$ from both sides of the second equation. We get

$color(red)(y=-x+2)$

We can now plug this value into the blue equation. We get

$9x-5color(blue)((-x+2))=21$

Simplifying gives us

$9x+5x-10=21$

$=>14x=31$

$=>x=31/14$

We can plug this into the red equation to get

$y=-color(red)(31/14)+28/14$

$y=-3/14$

Therefore, our solutions are

$(31/14,-3/14)$

Hope this helps!

How do you solve the following system?: 9x -5y =21, -x -y = -29x -5y =21, -x -y = -2