A squared + b squared = c squared
        
             
        
        
        
Answer:
I would be 7 gallons used and 5 gallons left
Step-by-step explanation:
multyply 1.75 times 4 hours equal 7 then 12-7=5 is the total of gallons left 
Hope this helps 
 
        
                    
             
        
        
        
Answer:
2/7x +3=9
x=21
Step-by-step explanation:
Let the unknown be x.
Take 3 to the other side so: 2/7 multiplied by x= 6
Divide 6 by 2/7 to get the answer;
Therefore x=21
Sub back into equation to check answer.
 
        
                    
             
        
        
        
Answer:
Explanation: 
15 goes into 60, 4 times (1 fourth is equal to 25%).
15 goes into 75, 5 times (1 fifth is equal to 20%)
So 75 is one fifth more because it has a value of 15 more, and 60 is 1 fourth less than 75 because its value is more minuscule and less is more.
If you don't understand this was quite the challenge to explain. 
 
        
             
        
        
        
Answer:
I think the equation that best represent the relationship between r and s is A. s=1/6r