Answer:
Hey what'sup? 
You need to dig a little in, for what it's actually meaning 
Here the total is 720 right? 
Which came from the materials and the labors work in hourly basis 
So it's like 
Cost of the material + no of hours = bill 
We don't know what the no of hours are, so let's assume it as 'x' 
Hence the required equation is 
375+35*x=720
35*x = 720-375
35*x = 345
Therefore x=345/35 =9.8 
Therefore they worked for 9.8 hours or approximately 10 hours 
Peace out 
 
        
             
        
        
        
True because the 8 meters can be split up in 2 qnd
        
                    
             
        
        
        
Answer:x=143
Step-by-step explanation: set 128=X-15 add 15 to both sides