Find the 6th Term -3 , 3 , 9 , 15 , 21

This is an arithmetic sequence since there is a common difference between each term. In this case, adding ${\displaystyle 6}$ to the previous term in the sequence gives the next term. In other words, ${\displaystyle a_n=a_1+d(n-1)}$.

Arithmetic Sequence: ${\displaystyle d=6}$

This is the formula of an arithmetic sequence.

Substitute in the values of ${\displaystyle a_1=-3}$ and ${\displaystyle d=6}$.

Subtract ${\displaystyle 6}$ from ${\displaystyle -3}$.

Substitute in the value of ${\displaystyle n}$ to find the ${\displaystyle n}$th term.

Multiply ${\displaystyle 6}$ by ${\displaystyle 6}$.