How do you solve the following system: y = 3x – 12, -x+y=5?

$x = \setminus \frac{17}{2} , y = \setminus \frac{27}{2}$

Explanation:

substituting value of $y$ from $y = 3 x - 12$ into $- x + y = 5$ we get
$- x + 3 x - 12 = 5$
$2 x = 5 + 12$
$x = \setminus \frac{17}{2}$
Substituting $x = \setminus \frac{17}{2}$ in $y = 3 x - 12$
$y = 3 \setminus \cdot \setminus \frac{17}{2} - 12$
$= \setminus \frac{27}{2}$
$\setminus \therefore x = \setminus \frac{17}{2} , y = \setminus \frac{27}{2}$