Arithmetic operation between two number

predicates
   start.
   sum.
   divide.
clauses
    start:- sum ,divide.
    sum:-
       X = 5,
       Y = 6,
       S = X+Y,
       write(X," + ",Y, " is ",S).
    divide:-
       F=9,
       U=3,
       D=F div U,
       write("\n",F," Divide ",U, " = ",D).

goal
start.