How do solve the following linear system?:  4x-2y=2 , x-7y=4 ?

Dec 16, 2015

I found:
$x = \frac{3}{13}$
$y = - \frac{7}{13}$

Explanation:

Isolate $x$ from the second equation and substitute it into the first:

$x = 4 + 7 y$

and:

$4 \left(\textcolor{red}{4 + 7 y}\right) - 2 y = 2$

solve for $y$:
$16 + 28 y - 2 y = 2$
$26 y = - 14$
$y = - \frac{14}{26} = - \frac{7}{13}$
sustitute back into:
$x = 4 + 7 y = 4 - 7 \left(\frac{7}{13}\right) = \frac{52 - 49}{13} = \frac{3}{13}$