Question

What is a descending arithmetic sequence?

Answer 1

It's a sequence of numbers that go down in a regular, linear fashion.

Explanation:
An example is \(10,9,8,7, \ldots\) that goes down 1 every step or step \(=-1\).
But \(1000,950,900,850 \ldots\) would also be one, because this goes down 50 every step, or step \(=-50\).
These steps are called the 'common difference'.

Rule:
An arithmetic sequence has a constant difference between two steps. This can be positive, or (in your case) negative.