How do you solve $7 x + 6 y = - 23$ $7x+ 6y=-23$ and $- 9 x + y = 47$ $-9x+ y=47$ using substitution?

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Answer 1 · 2016-05-27T22:11:16

$x = - 5 and y = 2$ $x = -5 and y = 2$

First, change the second equation to be $y = ....$
So, we have the equations:

$7x + 6y = -23 " " and y = 9x + 47$

In the first equation, replace y by $(9x + 47)$

$7x + 6(9x + 47) = -23$

$7x + 54x + 282 = -23$

$61x = -305$

$x = -5$

In the second equation, use $x = -5$

$y =9(-5) + 47 rArr y = 2$

Check for $x = -5 and y = 2$

$7(-5) + 6(2)$
$-35 +12 = -23$

How do you solve 7x+ 6y=-237x+6y=−237x+ 6y=-23 and -9x+ y=47−9x+y=47-9x+ y=47 using substitution?