2.12-2. The system described by the equations 1)= [1 0,5] × (k) + [ i ]u(k) x(k + 1) y(k) = [12]x(k) is excited by the initial conditions x(0) = [-1 2] with u(k) = 0 for all k. (a) Use (2-89) to solve for x(k), k ≥ 0. (b) Find the output y(z). (c) Show that (k) in (a) satisfies the property (0) = I. (d) Show that the solution in part (a) satisfies the given initial conditions.