You inverse for the matrix is correct, but I think there are simpler and more efficient ways to invert a matrix. With that said I think you just made multiplication error
when you multiplied the column vector by the inverse. It should give
I'm trying to solve the following system of equations by matrix inversion, however when I substitute back my final solutions for x,y,z into the equations, one of them doesn't work. I checked everything a couple of times but I can't find the mistake.
Q: Solve the system of equations by matrix inversion if possible:
and here is the solution: ImageShack Album - 6 images