Answer:
= 22 - 7n
Step-by-step explanation:
There is a common difference d between consecutive terms, that is
8 - 15 = 1 - 8 = - 7
This indicates the sequence is arithmetic with explicit formula
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = 15 and d = - 7 , then
= 15 - 7(n - 1) = 15 - 7n + 7 = 22 - 7n ← explicit formula
b(n) = 15 - 7(n - 1)
15 is the y-intercept
-7 is the slope
A
-2 11/20
- 2/5 - 5/4 + (-9/10)
- 2/5 - 5/4 = 1 13/20
1 13/20 + (-9/10) = -2 11/20