-40
Explanation:
(-7+2) would equal -5, then you multiply -5 by 8 and you get -40.
        
                    
             
        
        
        
A^2+b^2=c^2 so 4(4) +3(3) is 16+9= 25 and the square root of that is 5.
        
             
        
        
        
If we are supposed to give you like a life situation that matches the equation then I have one:
You have 42 watermelons and you need to divide them into equal groups. Let n equal the number of watermelons in each group. There are 6 groups in total. How many watermelons are in each group? (solve for n).
If this is not what you were looking for then my apologies.
        
             
        
        
        
N = 9
explanation: If you tilt triangle FGH to where it matches triangle PQR, 9 is matched with N.
more help: 
Q = G
10.5 = 7
P = F 
H = R
4 = 6
9 = N