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 .

It is really easy to figure out using this formula I have attached below with clear example.
a1 is the  first term
n = number of the term
 d = the difference you need.

Then you can go with a flow like this 
a29 = 47 + (29 - 1)(-2) a29 = 47 + (28)(-2) a29 = 47 + (-56) a29 = 47 - 56 a29 = -9