How do solve the following linear system?:  4x=-11+y , -x+3y=-5 ?

Sep 7, 2017

From $- x + 3 y = - 5$, $x = 3 y + 5$

Hence,

$4 \cdot \left(3 y + 5\right) = y - 11$

$12 y + 20 = y - 11$

$11 y = - 31$ or $y = - \frac{31}{11}$

Thus, $x = 3 \cdot \left(- \frac{31}{11}\right) + 5 = - \frac{38}{11}$

Explanation:

1) I found $x$ in terms of $y$ from second equation.

2) I plugged $x$ into first one for findind $y$.

3) I found $x$.