The reason question 6 is -8 is because of the distance in between each number, e.g -7 and -15. This is not to be confused with + 8 each time that would make the sequence 9, 18, 27.
Question 7:
The way we solve this question is using the nth term rule, whatever is before the n is the times tables we follow. So if it is 2n the sequence would be 2, 4, 6, 8 etc. However when we add something like the -2 we do the 2 times tables but this time we -2 for each one. Example: 2 - 2 = 0 so the first number of the sequence is 0, Example 2: 4-2 = 2 so the second number of the sequence is 2.
