The first term in the sequence 5, 7, - 7, ... is 5. Each even-numbered term is 2 more than the previous term and each odd-numbered term, after the first, is (-1) times the previous term. For example, the second term is 5+2 and the third term is (-1) * 7. What is the 255th term of the sequence?

Step-by-step explanation:

According to the condition, your terms are arranged as

5, 7, - 7,-5, 5, 7, - 7, 5, - 5, ...

So one loop will have 4 terms: 5, 7, - 7. - 5

Hence after 63 loops, the new loop has only 3 terms. That means the last loop will be 5, 7,-7. In other words, the 255th term will be - 7