Pearson Algebra 1 Common Core, 2011
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Pearson Algebra 1 Common Core, 2011 View details
7. Arithmetic Sequences
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Exercise 47 Page 279

Substitute 2, 4, and 11 for n.

Second: 2
Fourth: 12
Eleventh: 47

Practice makes perfect

To find certain terms in a sequence described by an explicit formula, substitute the number of the desired term into the given formula to get the term's value. A(n)=-3+(n-1)(5)We can find the second, fourth, and eleventh terms of the sequence by substituting 2, 4, and 11 for n in the above formula.

A(n)=-3+(n-1)(5)
A( 2)=-3+( 2-1)(5)
A(2)=-3+(1)(5)
A(2)=-3+(5)
A(2)=-3+5
A(2)=2

Now, let's do the same thing for the fourth and eleventh terms.

n^(th) term -3+(n-1)(5) A(n)
2 -3+( 2-1)(5) 2
4 -3+( 4-1)(5) 12
11 -3+( 11-1)(5) 47

The second, fourth, and eleventh terms are 2, 12, and 47.