Answer:
17.
Step-by-step explanation:
one dash is equal to 2. so just go by twos
So, we know the sum of the first 17 terms is -170, thus S₁₇ = -170, and we also know the first term is 2, well

well, since the 17th term is that much, let's check what "d" is then anyway,
Answer:
c will be the answer mark me brainliest