We have to use pythagorean theorem. The equation is 

 so we plug in the numbers (hypothenuse is always C in the equation) 

 now we solve:

 Exponents 

 Subtract
a=6 Square Root
x=6 Answer
 
        
        
        
Answer:
C
Step-by-step explanation:
 
        
             
        
        
        
0.04, or 4 hundredths is 10 percent of 0.40
10 times 0.04 gives you 0.40
        
                    
             
        
        
        
They will be 15 miles apart after one hour if they left the same point at the same time.
<h3>How do we measure and calculate the distance in Geometry?</h3>
The distance between two points in geometry can be calculated by using the Pythagoras theorem.
Mathematically, the Pythagoras theorem can be expressed as:

where;
- x and y are opposite and adjacent sides respectively.



d = 15 miles  
Therefore, we can conclude that they will be 15 miles apart after one hour if they left the same point at the same time.
Learn more about calculating the distance between two points here:
brainly.com/question/7243416
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