Respuesta :

Answer:

The 19th term is 99.

Step-by-step explanation:

We can write a direct formula and use it to find the 19th term. Recall that the direct formula for an arithmetic sequence is given by:

[tex]x_n = a + d(n-1)[/tex]

Where a is the initial term and d is the common difference.

Since the first term is 9 and the common difference is 5:

[tex]\displaystyle x _ n = 9+5(n-1)[/tex]

To find the 19th term, let n = 19. Thus:

[tex]x_{19} = 9+5(19-1)[/tex]

And evaluate:

[tex]\displaystyle \begin{aligned} x_{19} &= 9+5(18) \\ &= 9+90 \\ &= 99\end{aligned}[/tex]

The 19th term is 99.