Answer:
42 seconds
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
The viniculum in a fraction represents subtraction with exponents. 
Subtracting exponents gives us  3^12/3^8 * 3^2
Simplifying gives 3^12/3^10. Then, we can achieve 3^12 - 3^10. 
This equals 3^2.
3^2 = 9.
So 9 is the answer of your question. 
 
        
             
        
        
        
Answer:
30.2
Step-by-step explanation:
cos(58) = 16/BC
BC = 16/cos(58) = 30.2
 
        
                    
             
        
        
        
Answer:
x = 7.8
Step-by-step explanation:
a^2 + b^2 = c^2
4^2 + 2^2 = c^2
16 + 4 = c^2
c^2 = 20
c = 4.5
a^2 + b^2 = c^2
a^2 + 4.5^2 = 9^2
a^2 + 20.25 = 81
a^2 = 81 - 20.25
a^2 = 60.75
a = 7.8