Answer:
9a+6b
Step-by-step explanation:
4a+7b+5a-b
First figure out the  a's 4a + 5a = 9a
Then do b's (Remember, if there is no number by the letter then it is 1) 
7b - 1b = 6b
So for this to be simplified the answer is 9a+6b
 
        
             
        
        
        
Banana nanznznananannanakakaka
        
             
        
        
        
Half.
When you divide something by two, you halve its value.
        
             
        
        
        
Answer:
it is 1/4 
Step-by-step explanation:
 
        
             
        
        
        
Answer:
1/81
Step-by-step explanation: