Isn’t it already simplified?... or am i stupid.
        
                    
             
        
        
        
Answer:
the student in question bought 3 large notebooks and 3 small notebooks
Step-by-step explanation:
the easiest way to explain how to do this is by recognizing that the student bought $54 worth of notebooks- which is not divisible by 10 easily. that means, we should subtract 8 from 54 until we get a number that IS divisible
54 - 8 = 46 (one small notebook)
46 - 8 = 38 (two small notebooks)
3 8 - 8 = 30 (three small notebooks)
then, divide 30 by 10 to see how many large notebook the student bought.
30/10 = 3
the student in question bought 3 large notebooks and 3 small notebooks
 
        
             
        
        
        
2.40
5.40-2.40= 3 (price of 2 sodas)
8.70 - 7.20 = 1.5 (price of 1 soda)
The soda prices match up so a hamburger is 2.40
        
                    
             
        
        
        
7^0=1
7^1=7
7^2=7*7=49
7^3=7*7*7=343
etc... etc...