Answer: x(-3x+2)
Step-by-step explanation: (f+g)(x) is basically adding the two functions together.
[tex]-3x^{2} + x - 3 + x + 3\\-3x^{2} +2x\\x(-3x+2)[/tex]
Frist step:
Add both functions
Second step:
Combine like terms
Third step:
factor out the x to completely simplify