Answer:
7Σn=1 (-2n - 2)
Step-by-step explanation:
Sigma notation:
The top number is stop at n = 7 (inclusive)
The bottom number is start at n = 1
The equation is the expression for each term in the sum
Find explicit formula
d = -2, a₁ = -4
-4 - 2(n - 1)
-4 - 2n + 2
-2n - 2
7 goes on top of Σ
n = 1 goes on the bottom of Σ
-2n - 2 goes to the right of Σ
