Answer
middle term = $-7$
Work Step by Step
With arithmetic sequences that have three consecutive terms, the middle term can be found by taking the arithmetic mean of the two terms that are given, which is given by the formula:
middle term = $\frac{x + y}{2}$
Substitute the values given into the formula:
middle term = $\frac{-15 + 1}{2}$
Add to simplify:
middle term = $\frac{-14}{2}$
Simplify the fraction:
middle term = $-7$
