Question

Write an equation for the nth term of the arithmetic sequence. Then find a 30

Answer 1

Answer:

The nth term is given by: $a_n = -9 + 3(n-1)$

The 30th term is 78.

Step-by-step explanation:

Arithmetic sequence:

The nth term of an arithmetic sequence is given by:

$a_n = a_1 + (n-1)d$

In which $a_1$ is the first term and d is the common difference between terms.

-9, -6, - 3,0

This means that $a_1 = -9, r = -6 - (-9) = -6 + 9 = 3$. So

$a_n = -9 + 3(n-1)$

30th term:

$a_30 = -9 + 3(30-1) = -9 + 87 = 78$

The 30th term is 78.