SOLUTION: Is my answer correct? I am supposed to find the first five terms and the tenth term given the explicit formula for an arithmetic sequence. an = -10 – 3(n – 1) -16,-19,-22,-

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Question 1008763: Is my answer correct?
I am supposed to find the first five terms and the tenth term given the explicit formula for an arithmetic sequence.
an = -10 – 3(n – 1)
-16,-19,-22,-25,-28
Tenth term:-43

Found 3 solutions by fractalier, stanbon, MathTherapy:
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
Not quite.
a1 = -10
a2 = -13
a3 = -16
a4 = -19
a5 = -22
a10 = -10 - 3(10-1) = -10 - 3(9) = -37

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the first five terms and the tenth term given the explicit formula for an arithmetic sequence.
a(n) = -10 – 3(n – 1)
a(1) = -10 - 3*0 = -10
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a(2) = -10 - 3(2-1) = -10 -3 = -13
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a(3) = -10 - 3(3) = -10-9 = -19
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etc..
a(10) = -10 - 2(10-1) = -10-2*9 = -28
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Cheers,
Stan H.
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Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Is my answer correct?
I am supposed to find the first five terms and the tenth term given the explicit formula for an arithmetic sequence.
an = -10 – 3(n – 1)
-16,-19,-22,-25,-28
Tenth term:-43
From the AP formula for a term, n: a%5Bn%5D+=+a%5B1%5D+%2B+%28n+-+1%29d, it's obvious from the given equation: a%5Bn%5D+=+-+10+-+3%28n+-+1%29 that term 1, or a%5B1%5D+=+-+10, and d,
or the common difference is: - 3
2nd term: Term 1 + d(2 - 1), or - 10 - 3(1), or highlight_green%28-+13%29
3rd term: Term 1 + d(3 - 1), or - 10 - 3(2), or highlight_green%28-+16%29
4th term: Term 1 + d(4 - 1), or - 10 - 3(3), or highlight_green%28-+19%29
5th term: Term 1 + d(5 - 1), or - 10 - 3(4), or highlight_green%28-+22%29
10th term: Term 1 + d(10 - 1), or - 10 - 3(9), or highlight_green%28-+37%29