(a) If x = [x1 x2 . . . Xn]' and y = [y1 y2 . . . ya]' are solutions to (2.3.4), show that Z = x + y and w = cx are also solutions, where c is an arbitrary scalar. (b) Is the result of (a) true when x and y are solu- tions to the nonhomogeneous system Ax = b? Explain.\f