(-9) - (-2) = -7
that should be the answer you subtract 
        
             
        
        
        
Answer:
D
Step-by-step explanation:
Just look at the symbols lol
 
        
             
        
        
        
The sum will be: 
sigma(i = 1 to infinity, 30*(2/5)^i) 
->

Which is equal to 30/(3/5) = 50
 
        
        
        
Answer: See each part below.
Part A: The y-intercept is the first value, or 12. That means that they bird is 12 miles from its nest when the time started.
Part B: The average rate of change is the slope. From 1 to 3 hours, the bird went from 20 to 36 or 16 miles. 16 miles in 2 hours is the same as 8 miles in 1 hour.
Part C: To find the extent of the domain, write and solve the following equation for 172 miles.
172 = 8x + 12
160 = 8x 
20 = x
The domain will go up to 20 hours.
        
             
        
        
        
Answer:
(x+1) (x-1) (x+2) (x-2)
Step-by-step explanation:
<u>Let u = x^2</u>
= u^2 - 5u + 4
<u>(Factor u^2 - 5u + 4)</u> 
= (u-1) (u-4)
<u>Substitute back u = x^2</u>
= (x^2 -1 ) (x^2 - 4)
<u>Factor x^2 - 1 and x^2 -4</u>
= (x+1) (x-1) (x+2) (x-2)
Hope this helped... :) 
If you need to see the work for yourself, copy/paste this link
https://www.symbolab.com/solver/factor-calculator/factor%20x%5E%7B4%7D%20%E2%88%92%205x%5E%7B2%7D%20%2B%204%20