plz answer this ASAP

We look at a Social Network, where the values at nodes are opinions which can be both positive or negative. Some members have fixed opinions already and not influenced by their friends. The rule is that the remaining people have the sum of the opinions of their friends. We still miss the opinions of three people x, y, z. x-y-z = 2 |-x+y-z = -6 |-x-y + z = -4 a. Write the augmented 3 x 4 matrix B =[A[b] which belongs to the system and find its row reduced echelon form. We ask you here to document which row reduced echelon form steps you do. b. What are the solutions to the system of linear equations