How do you solve the following system?: $-9x -8y =-3, 2x -2y = -4$

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Answer 1 · 2016-02-12T16:58:17

The solution for the system of equations is:
$color(green)(x = -13 / (17)$

$color(green)(y =21/17$

$-9x-color(blue)(8y)=-3$ .......equation $(1)$

$2x-2y = -4$ , multiplying this equation by $4$
$8x-color(blue)(8y) = -16$ ..........equation $(2)$

Solving by elimination

Subtracting equation $2$ from $1$ :

$-9x-cancelcolor(blue)(8y)=-3$
$-8x +cancelcolor(blue)(8y) = 16$

$-17x = 13$

$color(green)(x = -13 / (17)$

Finding $y$ from equation $1$

$-9x-color(blue)(8y)=-3$

$-9x+ 3 = 8y$

$-9 xx color(green)( -13 / (17))+ 3 = 8y$

$117 / (17)+ 3 = 8y$

$117 / (17)+ 51/17 = 8y$

$168/17 = 8y$

$y =168/(17 xx 8)$

$color(green)(y =21/17$

How do you solve the following system?: -9x -8y =-3, 2x -2y = -4-9x -8y =-3, 2x -2y = -4