SOLUTION: The arithmetic sequence x,2x-20,3x-28,... has D1=-16. What is the formula for the nth term ? I said tn= -16+12 but was marked wrong :(

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Question 118445: The arithmetic sequence x,2x-20,3x-28,... has D1=-16. What is the formula for the nth term ?
I said tn= -16+12 but was marked wrong :(
Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
Second term - First = d
2x - 20 - x = d
x - 20 = d
The sequence is not arithmetic ...