SOLUTION: Find the indicated term of the arithmetic sequence: 25th term: 9, 2, -5, -12...

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Question 930941: Find the indicated term of the arithmetic sequence: 25th term: 9, 2, -5, -12...
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
a%5B1%5D=9, a%5B2%5D=2

d=a%5B2%5D-a%5B1%5D=2-9=-7

a%5Bn%5D=a%5B1%5D%2B%28n-1%29d

a%5B25%5D=9%2B%2825-1%29%28-7%29

a%5B25%5D=9%2B%2824%29%28-7%29

a%5B25%5D=9%2B%28-168%29

a%5B25%5D=-159

Checking:

   9,    2,   -5,  -12,  -19, -26,  -33,  -40,  -47,  -54, 
 -61,  -68,  -75,  -82,  -89, -96, -103, -110, -117, -124,
-131, -138, -145, -152, -159. 

Edwin