F(g(x)) means you take the g function and put it into x in the f function.  He took the function and put it into the g, which was the incorrect order.  He should have had this: 
 
        
                    
             
        
        
        
Answer:
x=-27
Step-by-step explanation:
-0.57x+0.27x = 8.1
-0.3x = 8.1
x = -8.1/0.3
x = -27
 
        
                    
             
        
        
        
Answer:
I believe that  the answer is A or the first choice.
Step-by-step explanation:
because the rule for x is +1 and its y is the only one with a rule.
The rule is +1/2
 
        
             
        
        
        
Answer:
Ty, you too!
Step-by-step explanation:
Hope you have a good day.