How do you solve the following system: $4x-5y-23=0 , -2x=6y+18$ ?

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Answer 1 · 2016-03-30T08:38:33

$x = 1.41, y = -3.47$

For the first equation, start by adding $23$ to both sides, so that:

$4x - 5y = 23$

Then for the second equation, subtract $6y$ from both sides, so that:

$-2x - 6y = 18$

Then solve for $y$ by multiplying the second equation by $2$ on both sides and adding the two equations:

$4x - 5y = 23$
$+2*(-2x - 6y) = 2*18$

This gives:

$-17y = 59$ , so $y = -3.47$

Then, to solve for $x$ , multiply both sides of the first equation by 6 and both sides of the second equation by $-5$ and add them:

$6*(4x - 5y) = 6*23$
$+5*(2x - 6y) = -5*18$

This gives:

$34x = 48$ , so $x = 1.41$

You can check your answers by substituting $1.41$ for $x$ and $-3.47$ for $y$ .

How do you solve the following system: 4x-5y-23=0 , -2x=6y+18 4x-5y-23=0 , -2x=6y+18 ?