How do you solve this system of equations: $4x + 6y = - 78 and x - y = - 2$ ?

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Answer 1 · 2018-05-03T02:29:54

$x=-9$ and $y=-7$

$x−y=−2$ ; $4x+6y=−78$

Step 1: Solve $x−y=−2$ for $x$ :

$x−y (+y) =−2 (+y)$
(Add $y$ to both sides)

$x=y−2$

Step 2: Substitute “ $y−2$ ” for “ $x$ ” in $4x+6y=−78$ :

$4x+6y=−78$
$4(y−2)+6y=−78$
$10y−8=−78$
(Simplify both sides of the equation)

$10y−8 (+8)=−78 (+8)$
(Add $8$ to both sides)

$10y=−70$
$10y/ (10)=−70/ (10)$
(Divide both sides by $10$ )

$y=−7$

Step 3: Substitute “ $−7$ ” for “ $y$ ” in $x=y−2$ :
(Simplify both sides of the equation)
$x=y−2$
$x= (−7) −2$

$x=−9$

$x=-9$ and $y=-7$

How do you solve this system of equations: 4x + 6y = - 78 and x - y = - 24x + 6y = - 78 and x - y = - 2?