Find the 17th term of the sequence

a_18 = 32, d=-4

Question

Find the 17th term of the sequence

a_18 = 32, d=-4

anonymous · Answer

18a = 32
32 / 18 = a
a = ?

angelwings996 · Answer

1.78

anonymous · Answer

That solves for a. I've no clue what you mean by 17th term, as it's not a sequence, and I don't see the point to value d.

angelwings996 · Answer

I'm not sure either, that's what the problem in the textbook is asking

angelwings996 · Answer

It says in the back of the book that it is 36

anonymous · Answer

Quite a poorly worded question.

angelwings996 · Answer

I had a problem earlier asking for the 32nd term for the sequence, but it actually gave me a list of numbers as this one doesn't

anonymous · Answer

general form for arithmetic sequence: $$a_{n}=a_{1}+(n-1)d$$
since we know 18th term we can substitute:
$$(32)=a_{1}+((18)-1)(-4)$$
solve for a1

angelwings996 · Answer

Uhmm...I got -2.125 ?

angelwings996 · Answer

Did I do it wrong?

anonymous · Answer

$$32 = a_{1} - 68$$
$$a_{1} = 100$$

angelwings996 · Answer

Ohh, I wasn't paying attention and divided them instead of adding

angelwings996 · Answer

@brusmack what do I do now?

anonymous · Answer

now you can fill in the general equation
$$a_{n}=100+(n-1)(-4)$$

anonymous · Answer

use n=17 for the 17th term

angelwings996 · Answer

Okay, so would it then be like 
$$a_{17}=100+(18-1)(-4)$$

angelwings996 · Answer

Wait 17 not 18

anonymous · Answer

yep, so you should get a(17)=36

angelwings996 · Answer

Okay, thank you so much!!

anonymous · Answer

no problem