Solve for x and Find t10 | Arithmetic Sequence

Thread starter priscilla89
Start date Dec 27, 2010
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Arithmetic Sequence

AI Thread Summary

To solve for x in the arithmetic sequence (2 - x), (-6 + 2x), (x + 2), the common difference d is calculated as d = (-6 + 2x) - (2 - x) and also as d = (x + 2) - (-6 + 2x). Setting these two expressions for d equal allows for solving for x. Once x is determined, the 10th term t10 can be found using the formula an = a1 + (n - 1)d. The discussion emphasizes the importance of correctly identifying the common difference in arithmetic sequences.

Dec 27, 2010

priscilla89

Homework Statement

For the arithmetic sequence (2 - x),
(-6 + 2x), (x + 2), solve for x and find t10.

Homework Equations

an = a1 + (n - 1) d

The Attempt at a Solution

Would I have to start off like this below:::

an = a1 + (n - 1) d

d = (-6 + 2x)-(2 - x) = (x + 2)-(-6 + 2x)

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Dec 27, 2010

graphene

yes.

Dec 27, 2010

priscilla89

Ok thanks

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