Big Ideas Math Integrated I, 2016
BI
Big Ideas Math Integrated I, 2016 View details
Maintaining Mathematical Proficiency
Continue to next subchapter

Exercise 10 Page 271

What is the first term of the sequence? What is the common difference between terms? Use these values in the explicit equation for arithmetic sequences.

a_n=- 7n+29

Practice makes perfect
Explicit equations for arithmetic sequences follow a specific format. a_n= a_1+( n-1) dIn this form, a_1 is the first term in a given sequence, d is the common difference from one term to the next, and a_n is the nth term in the sequence. For this exercise, the first term is a_1= 22. Let's observe the other terms to determine the common difference d. 22- 7 →15- 7 →8- 7 → 1 ... By substituting these two values into the explicit equation and simplifying, we can find the formula for this sequence.
a_n=a_1+(n-1)d
a_n= 22+(n-1)( - 7)
a_n=22-7n+7
a_n=- 7n+29
The equation for the nth term of the given arithmetic sequence is a_n=- 7n+29.