Answer:
f(3) =-6
Step-by-step explanation:
If f(3) then simply replace every (x) in the equation with a 3 then solve.
f(3) = -(3)-3
f(3) = -3-3
f(3) =-6
f(3) =-6 is your final answer.
Hope this helps! If you have any questions on how I got my answer feel free to ask. Stay safe!