Question 393975
USE MATRICES LOL

[1 1 -1] [x] [2]
[2 1  1] [y]=[3]
[3 1  1] [z] [5]

let the first matrix be A , and the last one with the salutions be B

now just find the inverse of A, and multiple it by B (easiest done with a calculator)

and you'll get 
x = 2 
y = -.5
z = -.5