Solve the following eqauation system using Gauss eliminatiom method -w+x y + z = 2 - w+ x y + z = 0 4x-4y+4x=4 w-2x+2y-2z=-3

A commuter must travel from Ajax to Barrie and back every day. Four roads join the two cities. The commuter likes to vary the trip as much as posible, so she alwaysleaves and returns by different roads. In how many different ways can she make the round-trip?