Question

WILL GIVE BRAINLIEST AND FIVE STARS FOR CORRECT ANSWER
#2
Find an equation for the nth term of the arithmetic sequence.
-15, -6, 3, 12, ...

Answer Choices:
A: an = -15 + 9(n + 1)
B: an = -15 x 9(n - 1)
C: an = -15 + 9(n + 2)
D: an = -15 + 9(n - 1)

Answer 1

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General Formula for arithmetic series :
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an = a₁ + d(n – 1)

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Find equation :
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a₁ = -15 and d = 9,

 $a_n = -15 + 9(n-1)$

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Answer:  $a_n = -15 + 9(n-1)$ (Answer D)
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