Basically, you are going to evaluate 5n - 4 from n = 1 to n = 18. Don't forget to add as you evaluate.
I will get you started.
Let n = 1 and then n = 2.
5(1) - 4 + 5(2) - 4 + the rest
5 - 4 + 10 - 4 + the rest
1 + 6 + the rest
7 + the rest
Just continue the pattern. You will then let n be 3, 4, 5, etc all the way to 18.
