# How do you write an equation for the nth term of the arithmetic sequence: 7, 16, 25, 34, ...?

Mar 6, 2018

$9 n - 2$

#### Explanation:

$7 , 16 , 25 , 34 , \ldots$

here is one method

we note that each term of the sequence is obtained by adding $9$ to the previous term

tus

$7 , \left(7 + 9\right) , \left(7 + 2 \times 9\right) , \left(7 + 3 \times 9\right) , \ldots$

so teh nth term

is $7 + \left(n - 1\right) \times 9$

or
${n}^{t h} = 7 + 9 \left(n - 1\right)$

$= 7 + 9 n - 9 = 9 n - 2$