Hi, I need help with a question -

I need to use Gaussian elimination and back substitution to solve the following system:

0 + 4x2 – 3x3 = 3

-x1 + 7x2 – 5x3 = 4

-x1 + 8x2 - 6x3 = 5

Since the first pivotal position is 0, I interchange rows one and two before eliminating numbers below the pivot. I'm not sure what to do after that.

Thanks for any help.