Answer
Series: $8,3,-2,-7,-12....$
$a_{2}-a_{1}=-5$
$a_{3}-a_{2}=-5$
$a_{4}-a_{3}=-5$
$a_{5}-a_{4}=-5$
This sequence is an example of Arithmetic sequence.
Work Step by Step
Series: $8,3,-2,-7,-12....$
$a_{2}-a_{1}=-5$
$a_{3}-a_{2}=-5$
$a_{4}-a_{3}=-5$
$a_{5}-a_{4}=-5$
Each term, after the first is obtained by adding a fixed number $(-5)$ to the preceding terms.
This sequence is an example of Arithmetic sequence.