### Home > A2C > Chapter 12 > Lesson 12.3.1 > Problem 12-121

12-121.

Consider the series 8 + 1 + (−6) + (−13) + … + (−90). Homework Help ✎

How many terms are there?

What is the sum?

Write an expression for the sequence, and find *n* when *t*(*n*) = −90.

15