How do solve the following linear system?: $x - 3y = -6 , 10x - 7y = -18$ ?

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Answer 1 · 2016-01-27T14:13:19

${x,y}={-12/23,42/23}$

Solve by elimination

$x-3y=-6$
$10x-7y=-18$

We can eliminate $10x$ from the second equation by $x$ in the first equation if we multiply $x$ by $-10$ to get $-10x$

$rarr-10(x-3y=-6)$

$rarr-10x+30y=60$

Now add both of the equations

$rarr(-10x+30y=60)+(10x-7y=-18)$

$rarr23y=42$

$y=42/23$

Now substitute the value of y to the first equation

$x-3(42/23)=-6$

$x-126/23=-6$

$x=-6+126/23=(-138+126)/23=-12/23$

So, ${x,y}={-12/23,42/23}$

How do solve the following linear system?: x - 3y = -6 , 10x - 7y = -18 x - 3y = -6 , 10x - 7y = -18 ?