## Algebra 1: Common Core (15th Edition)

Pattern is "add 3 to the previous term." The next three terms are $12$, $15$ and $18$.
$3,6,9$ A pattern is "add 3 to the previous term". So the next three terms are $9 + 3 = 12$, $12 + 3 = 15$ and $15+3=18$.