Question

What is the explicit formula for this sequence? -8,-3,2,7,... A. an=-8+(n-1)(-5) B. an=-8+(n-1)5 C. an=12+(n-1)5 D. an=5+(n-1)(-8)

Answer 1

The answer is B

Explanation:

Answer 2

an = -8 + 5(n-1)

Explanation:

-8,-3,2,7

First find the common difference

Take the second term and subtract the first term

-3 - -8 = -3 +8 = 5

Check with the other terms

2 - -3 = 2+3 = 5

The common difference is 5

The formula for the arithmetic sequence is

an = a1 + d(n-1) where d is the common difference and a1 is the first term

an = -8 + 5(n-1)