Algebra Examples

$a_{n} = (5 n - 2) (4 n + 1)$

Step 1

Substitute in the value of $n$ to find the $n$ th term.

$a_{3} = (5 (3) - 2) (4 (3) + 1)$

Step 2

Multiply $5$ by $3$ .

$a_{3} = (15 - 2) (4 (3) + 1)$

Step 3

Subtract $2$ from $15$ .

$a_{3} = 13 (4 (3) + 1)$

Step 4

Multiply $4$ by $3$ .

$a_{3} = 13 (12 + 1)$

Step 5

Add $12$ and $1$ .

$a_{3} = 13 \cdot 13$

Step 6

Multiply $13$ by $13$ .

$a_{3} = 169$