YES(?,O(n^2))
TRS:
 {a b x -> b a x,
  a c x -> x}
 DUP: We consider a non-duplicating system.
  Trs:
   {a b x -> b a x,
    a c x -> x}
  Matrix Interpretation:
   Interpretation class: triangular
       [X1]    [1 1][X1]   [3]
   [c]([X0]) = [0 1][X0] + [0]
   
       [X1]    [1 3][X1]   [0]
   [a]([X0]) = [0 1][X0] + [1]
   
       [X1]    [1 1][X1]   [0]
   [b]([X0]) = [0 1][X0] + [2]
   
   
   Qed