Help me if you can: Here are the questions.

1) Sovle the system of equations by the Gaussian elimination method:

{ 2x + y - 3z = 1

{ 3x - y + 4z = 6

{ x + 2y - z = 9

2) Solver the system of equations by the Gaussian elimination method:

{ x - y + z = 17

{ x + y - z = -11

{ x - y - z = 9

Thanks in advance for any help!!!

Kasey