SOLUTION: Give an explicit rule for the nth term of the sequence: -8, 3, 14, 25, ….

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Question 1137602: Give an explicit rule for the nth term of the sequence:
-8, 3, 14, 25, ….
Found 2 solutions by josgarithmetic, MathLover1:
Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
n index of term
-8%2B%28n-1%2911

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

given:
-8,+3, 14, 25, ….
find differences:
-8…. 3…. 14…. 25
....11..... 11…. 11…
so, d=11
nth term formula:
a%5Bn%5D=a%5B1%5D%2B%28n-1%29%2Ad
plug in
a%5B1%5D=-8
d=11

a%5Bn%5D=-8%2B%28n-1%29%2A11=> an explicit rule for the nth term of the sequence, n starts from 1
check:
a%5B1%5D=-8%2B%281-1%29%2A11=-8%2B0%2A11=-8
a%5B2%5D=-8%2B%282-1%29%2A11=-8%2B1%2A11=3
a%5B3%5D=-8%2B%283-1%29%2A11=+-8%2B2%2A11=14
a%5B4%5D=-8%2B%284-1%29%2A11=-8%2B3%2A11=25