Problem 7. (1 point)
Find the set of solutions for the linear system
$2x_1 + 5x_2 - x_3 + x_4 = 17$
$-x_2 - 6x_3 - 13x_4 = -9$
$2x_3 + x_4 = 12$
If your answer includes any arbitrary parameters name them $s_1$, $s_2$, etc., as needed.
$(x_1, x_2, x_3, x_4) = (4 + \frac{59}{2}s_1, 3 - \frac{25}{2}s_1, 6 - \frac{1}{2}s_1, s_1)$
Note: You can earn partial credit on this problem.