How do solve the following linear system?: $x - y = 11, 2 x + y = 19$ $x-y=11 , 2x+y=19$ ?

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Answer 1 · 2016-01-17T14:20:39

$x = 10$ $color(blue)(x=10$
$y = - 1$ $color(blue)(y=-1$

$x - y = 11$ $x-color(blue)(y)=11$ ...............equation $1$ $1$

$2 x + y = 19$ $2x+color(blue)y=19$ ............equation $2$ $2$

Solving by elimination:

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

$x-cancelcolor(blue)(y)=11$

$2x+cancelcolor(blue)y=19$

$3x=30$

$x=30/3$

$color(blue)(x=10$

Finding $y$ from equation $1$ :
$x-y=11$

$x-11=y$

$10-11=y$

$color(blue)(y=-1$

How do solve the following linear system?: x-y=11 , 2x+y=19 x−y=11,2x+y=19 x-y=11 , 2x+y=19 ?