Find the common difference of an arithmetic sequence if the first term is -9 and the seventh term is -39.

Question

Quizplus · Accepted Answer

The common difference (d) in an arithmetic sequence can be found using the formula for the nth term: $a_n = a_1 + (n - 1)d$, where $a_n$ is the nth term, $a_1$ is the first term, and $n$ is the term number. Substituting the given values for the 7th term, we get $-39 = -9 + (7 - 1)d$, which simplifies to $-30 = 6d$. Solving for $d$ gives $d = -5$.

Find the Common Difference of an Arithmetic Sequence If the First