Answer:   It would be d and a
Step-by-step explanation:
 
        
             
        
        
        
Answer:
16
Step-by-step explanation:
Substitute (7) into the equation.
y= 1/4(15-(7))^2
 
        
             
        
        
        
Answer:
n+1=x-1
Step-by-step explanation:
as n goes up, x decreases by 1 each time
 
        
             
        
        
        
Answer:

Step-by-step explanation:
Given the expression  , to solve the expression, we need to write both scientific notation to the same power of 10.
, to solve the expression, we need to write both scientific notation to the same power of 10.

The expression above becomes  . On taking the difference;
. On taking the difference;

The final expression gives the right answer