How do you solve $3 x - y = 9$ $3x-y=9$ and $2 x + y = 1$ $2x+y=1$ ?

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Answer 1 · 2016-01-08T17:14:35

The solution for the system of equations is
$x = 2, y = - 3$ $color(blue)(x=2,y=-3$

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

$2 x + y = 1$ $2x +color(blue)(y)=1$ ......equation $(2)$ $(2)$

Solving by elimination

Adding equations $1$ $1$ and $2$ $2$

$3x-cancelcolor(blue)(y)=9$
$2x +cancelcolor(blue)(y)=1$

$5x =10$

$x=10/5$

$color(blue)(x=2$

Finding $y$ from equation $1$

$3x-y=9$

$3 xx 2 -y=9$

$6 -y=9$

$6 -9=y$

$color(blue)(y=-3$

How do you solve 3x-y=93x−y=93x-y=9 and 2x+y=12x+y=12x+y=1?