### Home > CCG > Chapter 8 > Lesson 8.1.2 > Problem8-21

8-21.

Write an equation for each of the following sequences. Homework Help ✎

1. $−30, −15, 0 \;...$

Is the sequence arithmetic or geometric?

Refer to the Math Notes box in 4.1.3 on sequences.

$a_n = 15(n − 1) − 30$

1. $9, 3, 1$

Is this an arithmetic or geometric sequence?
See part (a) for help.