Answer:
Step-by-step explanation:
triangle area = (length*width)/2
height(length): x
base(width): 8x
area = 45
8x^2=45
solve for x
 
        
             
        
        
        
You multiply three( # of shirts) and 15.90 ( price)
The answer is $47.70 is how much he spend
 
        
             
        
        
        
One way you could solve this is to just multiply the top and bottom out so that you get 9/81, reducing it by 9/9 to get 1/9 or option C.
Another way would be to do 

 since dividing numbers with exponents would be subtracting the bottom exponent from the top exponent, provided that the base number (in this case 3) is the same for both. For this method, you would get 

, which is equal to 1/9 or .1 repeating, the same answer that you'd get with the first method.
 
        
        
        
If you look at the chart (about the chores) you can find out everthing
        
             
        
        
        
No it is an irrational number because it is a decimal with repeating numbers.