This problem is for someone with advanced knowledge of matrices. This problem relates to orthogonality. Please write clearly (no cursive)

Problem 3. Let A be the incidence matrix of the digraph G given by a4 a3 V4 V3 V1 a2 U2 a5 a1 Let b = 5 -3 -1 -1 . Determine if the system Ax = b is consistent without finding A. Hint. We can find a basis of Null(AT ) without finding A. How would this basis help in determining if Ax = b is consistent