Question 97660:  even though we have our books in algebra... 
I do not understand what our teacher is tackling about... maybe he is so fast in discussing of the topics so that we can't relate to him... 
In our homework... i don't know what i am going to do because this topic is not yet discuss unto us but i want to learned it so i can get high score during our quizzes...i just want to know if how come the answer goes like this...an=2n-6?
 
our problem or exercise needed to solve is that: 
write a formula for the nth term of arithmetic sequence... 
==> -4,-2,0,2,4,... 
can you help me please... can you explain it to me?
 
it is not from the book... it's from our math teacher.. 
 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! write a formula for the nth term of arithmetic sequence... 
==> -4,-2,0,2,4,... 
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The formula for the nth term of an arithmetic sequence is 
a(n) = a(1)+(n-1)d 
a(1) is the 1st term of the sequence 
d is the difference between any term and the one before it. 
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Your Problem 
The 1st term is -4 
d = 2-0 = 2 
So the nth term is a(n)=-4+(n-1)*2 
a(n) = -4+2n-2 
a(n) = -6+2n 
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Cheers, 
Stan H. 
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