SOLUTION: if th 10th of an AP is double the 2nd find the 8th term given that a=7

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Question 1117673: if th 10th of an AP is double the 2nd find the 8th term given that a=7
Found 2 solutions by ikleyn, josgarithmetic:
Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.
Given that  WHAT ?


What this   "a=7"  means  and  how does it relate to the rest of the text ?

As this post is presented, it does not make sense.



Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
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if th 10th of an AP is double the 2nd find the 8th term given that a=7
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If thE 10th TERM of an AP is double the 2nd, find the 8th term given that a=7.
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General term, 7%2Bd%28n-1%29, for difference d and index n

7%2Bd%2A%2810-1%29=2%287%2Bd%2A%282-1%29%29
7%2B9d=2%287%2Bd%29
7%2B9d=14%2B2d
9d-2d=14-7
7d=7

highlight%28d=1%29-------common difference to get each successive term

Revising the general term, highlight%287%2B%28n-1%29%29.

FIND THE 8TH TERM
let n equal to 8.
7%2B%288-1%29
7%2B7
highlight_green%2814%29