I personally think its B but you gotta say if its either multiplication or addition or division 
 
        
                    
             
        
        
        
Answer:
21/5
Step-by-step explanation:
 
        
             
        
        
        
(5 Neighbors) x (($1.00 Box) + (? Plant) + ($3.00 Gloves)) = 42.50
5 x (1 + x + 3) = 42.50
Combine in parens. 
5 x (4 + x) = 42.50
Distribute. 
20 + 5x = 42.50
Subtract 20 from both sides. 
5x = 22.50
Divide both sides by 5. 
x = 4.50
Thats the cost of each plant. 
Check. 
5 x (1 + 4.50 + 3) 
5 x 8.50 = 42.50
        
             
        
        
        
F(x) = g(x)
3(2) - 4 = (2)² - 2
6 - 4 = 4 - 2
2 = 2
I just substituted all the values in the domain to see which one would work. That's not really the quickest way but that's the only way I know