The answer is 72.
You can figure this out using the Pythagorean theorem: C (78) squared - A (30) squared = B squared though since you already know the longest side. 
78 x 78 = 6084
30 x 30 = 900
6084-900= 5184
The square root of 5184 is 72.
        
             
        
        
        
4003052
 I hope this helps
        
             
        
        
        
Answer:
All of them are correct except for number 15
Step-by-step explanation:
Number 15 is D.
 
        
                    
             
        
        
        
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