Consider the system x − y = b1 2x + 3y = b2 3x + 2y = b3 What condition (if any) on b =   b1 b2 b3   is needed to ensure the system is solvable? For b =   4 −2 2  , find all solutions of the system using elimination and back substitution. Write your answer in the form v = vp + vn, where vp is a particular solution, and the null solution vn is a linear combination of special null solutions.