The common difference in an arithmetic sequence is –2 and the first term is 47. What is the 29th term?

A.

–9

B.

–11

C.

11

D.

18

Question

The common difference in an arithmetic sequence is –2 and the first term is 47. What is the 29th term?




A. 

–9 


B. 

–11 


C. 

11 


D. 

18

.sam. · Answer

Figure out the formula to find nth term

anonymous · Answer

how do  I do that?

texaschic101 · Answer

here is the formula : an = a1 + (n-1)d
a1 = your first term
n = number of the term to find
d = common difference

lets begin...
a29 = 47 + (29 - 1)(-2)
a29 = 47 + (28)(-2)
a29 = 47 + (-56)
a29 = 47 - 56
a29 = -9

any questions ?

texaschic101 · Answer

this might help... http://www.regentsprep.org/Regents/math/algtrig/ATP2/ArithSeq.htm

anonymous · Answer

okay ; will this be the formula for all the sequences?

texaschic101 · Answer

this is the formula for an arithmetic sequence and finding a certain term....not the sum and not geometric sequences

anonymous · Answer

okay thank you

texaschic101 · Answer

sure thing :)