HELP WITH THIS MATH!!! IM TIMED

Answer:
Table C)
Step-by-step explanation:
[tex]y=-x+3\\x+y=3\\Hence,\\Considering\ Table\ C\,\\Substituting\ x=-3,y=6\\6=3+3\\6=6 (LHS=RHS)\\\\Substituting\ x=0, y=3\\3=3 (LHS=RHS)\\\\Substituting\ x=3, y=0,\\0=-(3)+3\\0=0 (LHS=RHS)[/tex]