Question

What is the 32nd term of the arithmetic sequence where a1 = 12 and a13 = −60?

I can't seem to find the value of d no matter how hard I try and I keep getting weird answers.

Answer 1

So when a changed by 13 minus one (13-1), the number changed by negative 60 minus 12 (-60-12)

Answer 2

Wouldn't it change by positive 12 since a1 is positive and a13 is negative?

Answer 3

Would the difference happen to be -6 in this?

Answer 4

yes...d = -6

Answer 5

Okay, so then if I just subtract 12 by (32-1)(-6) would I get what I need? I'm not quite sure of the formula I need

Answer 6

Because I'm getting -174. Is that right?

Answer 7

I got -174 also. I never got to study this, so I just made up a formula

Answer 8

Alright, I think that's right, so I'll go with it. Thanks a bunch

Answer 9

We're looking for X, which is a32

So I did

X - (-60)
----------- = -6
32-13

X - a13
------------ = D
32-13

Then solved for D. And no problem, anytime

Answer 10

I mean solves for X

Answer 11

Alright, that gets -174 too. Thank you!