How do you solve the following system?: $- x - 3 y = 7, 4 x - 5 y = - 3$ $-x -3y =7, 4x -5y = -3$

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How do you solve the following system?: $- x - 3 y = 7, 4 x - 5 y = - 3$ $-x -3y =7, 4x -5y = -3$

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Answer 1 · 2015-11-12T06:27:49

$y = - \frac{25}{17}$ $y=-25/17$
$x = - \frac{44}{17}$ $x=-44/17$

Explanation:

I'm gonna use substitution for this one.
$- x - 3 y = 7$ $-x-3y=7$
$- x - 3 y - 7 = 0$ $-x-3y-7=0$
$- 3 y - 7 = x$ $-3y-7=x$

now substitute...

$4 x - 5 y = - 3$ $4x-5y=-3$
$4 (- 3 y - 7) - 5 y = - 3$ $4(-3y-7)-5y=-3$
$- 12 y - 28 - 5 y = - 3$ $-12y-28-5y=-3$
$- 17 y - 28 = - 3$ $-17y-28=-3$
$- 17 y = 25$ $-17y=25$

$y = - \frac{25}{17}$ $y=-25/17$

substitute into the equation above...
$- 3 y - 7 = x$ $-3y-7=x$
$- 3 (- \frac{25}{17}) - 7 = x$ $-3(-25/17)-7=x$
$\frac{75}{17} - 7 = x$ $75/17-7=x$
$\frac{75}{17} - \frac{119}{17} = x$ $75/17-119/17=x$

$- \frac{44}{17} = x$ $-44/17=x$

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How do you solve the following system?: $- x - 3 y = 7, 4 x - 5 y = - 3$ $-x -3y =7, 4x -5y = -3$

1 Answer

Explanation:

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Science

Math

Humanities

... and beyond

How do you solve the following system?: −x−3y=7,4x−5y=−3-x -3y =7, 4x -5y = -3

1 Answer

Explanation:

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Impact of this question

How do you solve the following system?: $- x - 3 y = 7, 4 x - 5 y = - 3$ $-x -3y =7, 4x -5y = -3$