Answer:
50
Step-by-step explanation:
Already done this
 
        
                    
             
        
        
        
16.  would be C since they both consist of the same variable to the same power
17. x-2x+7-9+4x
     c. 3x-2
18. -4(3a-5). You would multiply -4 by 3 a, and -4 by -5. It turns to
      -4(3a)-4(-5)
     a. -12a+20
        
             
        
        
        
This is a tricky question lol. 5/2 = 2.5 , which is half of 5 ... the picture will illustrate half of 5