Answer:
[tex]\boxed{\sf -2n+20}[/tex]
Step-by-step explanation:
Let’s find the common difference.
The common difference can be found by subtracting a term in the sequence with the previous term.
[tex]\sf d=16-18\\d=-2[/tex]
Apply formula for the [tex]\sf n^{th}[/tex] term of an arithmetic sequence.
[tex]\sf a_n=a_1+dn-d[/tex]
[tex]\sf a_1[/tex] is the first term of the sequence.
[tex]\sf d[/tex] is the common difference.
[tex]\sf a_n=18+-2n-(-2)[/tex]
[tex]\sf a_n=18+-2n+2[/tex]
[tex]\sf a_n=-2n+20[/tex]
