Find the Next Term 27 , 15 , 3 , -9 , -21

This is an arithmetic sequence since there is a common difference between each term. In this case, adding ${\displaystyle -12}$ to the previous term in the sequence gives the next term. In other words, ${\displaystyle a_n=a_1+d(n-1)}$.

Arithmetic Sequence: ${\displaystyle d=-12}$

This is the formula of an arithmetic sequence.

Substitute in the values of ${\displaystyle a_1=27}$ and ${\displaystyle d=-12}$.

Add ${\displaystyle 27}$ and ${\displaystyle 12}$.

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

Multiply ${\displaystyle -12}$ by ${\displaystyle 6}$.