Question

Find the sum of the first 9 terms of the sequence. Show all work for full credit.

2, -7, -16, -25, ...

Answer 1

we can see the sequence goes by decreasing 9 on each number

so the numbers are

2, -7, -16, -25, -34, -43, -52, -61, -70

so adding all these numbers we get

2-7-16-25-34-43-52-61-70

= -306


hope this helped