How do solve the following linear system?: $3x – 2y = 7 , 11x + 3y + 7 = 0$ ?

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Answer 1 · 2015-12-28T23:33:07

$3x-2y=7..........(i)$
$11x+3y+7=0 implies 11x+3y=-7............(ii)$
Multiply $(i)$ by $3$ and (ii) by 2 and add
$implies9x-6y=21$
$22x+6y=-14$

By addition we have
$31x+0=7$

$implies x=7/31$

Put $x=7/31$ in $(i)$

$implies 3(7/31)-2y=7$

$implies 21/31-2y=7$

$implies 2y=21/31-7$

$implies 2y=(21-217)/31$

$implies 2y=-196/31$

$implies y=-98/31$

How do solve the following linear system?: 3x – 2y = 7 , 11x + 3y + 7 = 0 3x – 2y = 7 , 11x + 3y + 7 = 0 ?