Find the ordered triplet (x,y,z) for the following system of equations:
x + 3y + 2z = 1
-3x - y + 5z = 10
-2x - 3y + 2z = 7
+874 (1) - (3) => 3x + 6y = -6
x + 2y = -3
(1) * 5 - (2) * 2 = (5x + 15y + 10z = 5) - (-6x - 2y + 10z = 20) => -x + 13y = -15 => x - 13y = 15
x + 2y = -3
x - 13y = 15
15y = - 18
y = - 6/5
x - 12/5 = -3
x = -15/5 + 12/5 = - 3/5
-3/5 + 3(-6/5) + 2z = 1
-3/5 - 18/5 + 2z = 1
-21/5 + 2z = 1
2z = 24/5
z = 12/5
(-3/5, -6/5, 12/5)
