Write a relation representing the information in the table.

Question

Input:
1
2
3
4
Output:
6
8
10
14
(Pretend those columns are next to each other)

I don't understand why it says 14 at the last output since I think it should be 12 (because it is the +4 rule, not +2).

My answer key says:
The output values increase by two for every increase of one in the inputs. This is the rate of change.
The starting point is 4.
The relation is 2x + 4 relates to x.

Answer 1

I dare ask, might this be an error in the workbook? Or am I getting something wrong?

Answer 2

I agree it should be 12
There are functions which could make it 14, but I doubt they would be appropriate for this problem.