Answer:
C) Tom did not distribute to both terms in parentheses.
Step-by-step explanation:
Addition within a paranthesis has a distributive property to the multiplier outside the paranthesis. Ignoring this will lead to a wrong value for the operation.
Answer:
8. Arithmetic Progression
9. 
Step-by-step explanation:
Given

Solving (8): Arithmetic or Geometric
We start by checking if it is arithmetic by checking for common difference (d).

This gives:



<em>Because the common difference is equal, then it is an arithmetic progression</em>
<em></em>
Solving (8):

To find f(9), we substitute 9 for n


We need to solve for f(8); substitute 8 for n


We need to solve for f(7); substitute 7 for n


We need to solve for f(6); substitute 6 for n


We need to solve for f(5); substitute 6 for n


From the function, f(4) = 25 and f(1) = 55.
So:













