direction y=x For each of the following systems, decide whether the origin is attracting, Liapunov stable, asymptotically stable, or none of the above. a) x=y, y=-4x. c) x = 0, y=x e) x=−x, j=−5y b) x=2y, y=x d) x=0,y=-y f) x = x, y = y