Answer:
B
Step-by-step explanation:
(f+g)(x) means f(x)+g(x), so you would just do 3x^3-2x^2+4x-5+6x-7.
You don't need to distribute the plus sign because it does nothing to 6x-7.
3x^3- stays constant due to no like terms
-2x^2- stays constant due to no like terms
4x+6x=10x
-5-7=-12
So it would be:
3x^3-2x^2+10x-12
