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Arithmetic sequence help!!!

Arithmetic sequence help!!!-example-1
User Luissimo
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2 Answers

5 votes

In order to solve, we must use the formula:
a_(n) = a_(1) + (n-1)d

a1 is the first term, n is the term position, and d is the common difference. We know that the first term is -1, the position we are trying to find is the 12th, and the difference is -6. So plug them all in.


a_(12) = -1 + (12-1)(-6)

So (12-1) = 11 and 11 (-6) = -66 now subtract 1

Answer is -67

User MaxH
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6.4k points
1 vote

Note that you are subtracting 6 each time.

5 terms have been shown.

Multiply -6 with 7 (as you are trying to find the 12th term)

-6(7) = -42

Add - 42 with -25

(-42) + (-25) = -67

(D) -67 is your answer

hope this helps

User Lmonninger
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