Question

What is the sum of a 17-term arithmetic sequence where the first term is 6 and the last term is -90?

Answer 1

The formula for the sum of an arithmetic series is:
\[\dfrac{n}{2} \left(a_1 + a_n\right)\]

Answer 2

i know the formula but i dont understand how to plug it into the formula

Answer 3

really? wow you said the same thing to me earlier

Answer 4

\(n\) is the number of terms. \(a_1\) is the first term. \(a_n\) is the last term.

Answer 5

n is the number of terms
a1 is your first term and an is the last term

Answer 6

why don't you do this one and we can check your answer