The question is really confusing me, I have no clue what its asking/how to do it. What I do know..

a) No solution occurs when the bottom row is all zeroes except for the constant. Like (0 0 0 4) because 0 = 4 is impossible.

b) A unique solution occurs when the leading 1s are in a perfect diagonal like:

(1 0 0 0)

(0 1 0 0)

(0 0 1 0)

c) And infinitely many solutions for anything else.

How would I go about doing this im completely confused