Problem 2 - (12 points) Let r E R be a real constant, and consider the linear system + 2y + Z 00 H 2x + 2y 2z = + 2y + 72 z (a) Show that for r = -1 the system has infinitely many solutions, and express the solutions in parametric form. (b) Show that for r = 1, the system has no solutions. (c) Show that if r # 1 and r -1, then the system has exactly one solution. Determine the solution. (The solution depends on r, don't be alarmed!)