Problem 1:
x + 2y - z = -2
x + z = 0
2x - y - z = -3
Problem 2:
2x - 3y - z = 13
-x + 2y - 5z = 6
5x - y - z = 49
The answer to problem 3 (that I got) is: x = -1, y = 0, z = 1
Is this correct?
For problem 4, do I use Gaussian elimination or Gauss-Jordan elimination?
Thanks in advance!