Answer:
![d=-6](https://img.qammunity.org/2023/formulas/mathematics/college/p4qijr9te8nu1gll1rkllaxtleofavj5uj.png)
![a_9=-49](https://img.qammunity.org/2023/formulas/mathematics/college/ioeyl0vj48pkgm3m14mwrvb34t5ncqqa52.png)
Explanation:
If the first term of a sequence is
and the second term is
, then each successive term in the sequence is
less than the previous term. The common difference is
(
).
The formula representing the arithmetic sequence is:
![a_n=-6n+5](https://img.qammunity.org/2023/formulas/mathematics/college/3wu35pz78p4upgbs3pj96nv3rtvjy1tt9k.png)
Therefore, the ninth term in the sequence is:
![a_9=-6(9)+5](https://img.qammunity.org/2023/formulas/mathematics/college/tiaf6jeg7fjo5ile4rl44h0epf4fhy6y8k.png)
![a_9=-54+5](https://img.qammunity.org/2023/formulas/mathematics/college/eo74jw1vb46y3wdlq6kknhaw2jybvnn3ce.png)
![a_9=-49](https://img.qammunity.org/2023/formulas/mathematics/college/ioeyl0vj48pkgm3m14mwrvb34t5ncqqa52.png)