Find the 107th term of the sequence -9, -5, -1, 3, 7

Your answer would be 415.

To find this we need to find the expression for the nth term of the sequence so we can substitute 107 in.

First you notice that each term is going up by 4 each time, which means that 4 is our n coefficient.

Then if we write the multiples of 4 above the sequence:

4, 8, 12, 16
-9, -5, -1, 3
We can see that the difference between each multiple of 4 and each term of the sequence is -13, because -9 - 4 = -13, -5 - 8 = -13, etc.

This means that your final expression is 4n - 13, and now you can substitute 107 in as n:
4(107) - 13 = 428 - 13 = 415

I hope this helps!