Exercise 51 Page 280

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)=-7+(n-1)(5)We can find the second, fourth, and eleventh terms of the sequence by substituting 2, 4, and 11 for n into the above formula.

A(n)=-7+(n-1)(5)

Substitute

n= 2

A( 2)=-7+( 2-1)(5)

SubTerm

Subtract term

A(2)=-7+(1)(5)

IdPropMult

Identity Property of Multiplication

A(2)=-7+(5)

RemovePar

Remove parentheses

A(2)=-7+5

AddTerms

Add terms

A(2)=-2

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

n^(th) term	-7+(n-1)(5)	A(n)
2	-7+( 2-1)(5)	-2
4	-7+( 4-1)(5)	8
11	-7+( 11-1)(5)	43

The second, fourth, and eleventh terms are -2, 8, and 43.