How do you solve the following system: $x-5y=-9, 6x+3y=-12$ ?

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Answer 1 · 2016-03-11T13:35:55

The solution for the system of equations is:
$color(blue)(x=-29/11$
$color(blue)(y = 14/ 11$

$x- 5y =-9$ , multiplying by $6$
$color(blue)(6x)- 30y =-54$ ........equation $(1)$

$color(blue)(6x)+3y =-12$ ..........equation $(2)$

Solving by elimination.

Subtracting equation $(2)$ from $(1)$ results in elimination of $color(blue)(6x):$

$cancelcolor(blue)(6x)- 30y =-54$
$-cancelcolor(blue)(6x)-3y = 12$

$-33y = -42$

$y = (-cancel42) / (-cancel33)$

$color(blue)(y = 14/ 11$

Finding $x$ from equation $1$ :

$x- 5y =-9$

$x=-9 + 5y$

$x=-9 + 5 * (14/11)$

$x=-9 + 70/11$

$x=-99/11 + 70/11$

$color(blue)(x=-29/11$

How do you solve the following system: x-5y=-9, 6x+3y=-12x-5y=-9, 6x+3y=-12?