Answer:

Step-by-step explanation:
We are given these following functions:


(f+g)(x)
We add the common terms. Thus:

Thus:

 
        
             
        
        
        
Three hundred four million, Eight hundred thousand Four hundred
and standard form is the way you wrote it, 304,800,400
        
             
        
        
        
9x-30 I’m pretty sure!
We are finding the difference, which means subtract! Nine times a number would be 9x and since it’s difference you would subtract it by 30.
        
             
        
        
        
The answer to your question 
is 12