Let A be the matrix given by 1 2 4 A = 1 0 2 3 1 3 0 (a) We are interested in a linear combination of the columns of A that gives the zero vector 0 0 Set up a system whose solution would give that linear combination. (b) Use the idea if elimination on the system from part (a) to turm A into an upper triangular matrix U, then use back substitution to solve the system. Explain whether the system has no solutions, one solution, or many solutions