Answer:
[tex]r = -9[/tex]
Step-by-step explanation:
Given
[tex]Sequence: 9,-81, 729,-6561...[/tex]
Required
Determine the common ratio
The common ratio r is calculated using:
[tex]r = \frac{T_n}{T_{n-1}}[/tex]
Let [tex]n = 2[/tex]
So, we have:
[tex]r = \frac{T_2}{T_{2-1}}[/tex]
[tex]r = \frac{T_2}{T_1}[/tex]
From the sequence:
[tex]T_2 = -81[/tex]
[tex]T_1=9[/tex]
So, the equation becomes
[tex]r = \frac{-81}{9}[/tex]
[tex]r = -9[/tex]
