Using Scientific Notebook, we find the inverse of A to be:

So the solution to the system of equations is:

Check:

22 + 2(-16) - (-16) = 6

3(22) + 5(-16) - (-16) = 2

-2(22) - (16) - 2(-16) = 4

So the solution is x = 22, y = -16 and z = -16.