Answer:
Concept: Ordinary Mathematics 
- Just a general tip: Zoom away further from the camera to capture the question clearer.
- Calculate the Total: 31 students 
- A= 4/31= 13%
- (A+B)/31 = 14/31 = 45%
- Can't see clearly what it says 
 
        
             
        
        
        
I also agree that the answers is the second one have a beautiful day:)
        
             
        
        
        
Answer:
do you have to expand it ?
 
        
                    
             
        
        
        
Start by multiplying the 9 out:
9(-6 + 8y) = -54 + 72y
Then, add the 7:
-54 + 72y + 7
Then simplify the whole thing:
-47 + 72y