Answer:
1094
Step-by-step explanation:
The sum of terms of a geometric series is given by ...
Sn = a1·(r^n -1)/(r -1)
You want the sum for ...
a1 = 2, r = -3, n = 7
Filling in the numbers, we get ...
S7 = 2·((-3)^7 -1)/(-3-1) = 2(-2188)/(-4)
S7 = 1094
Answer:
Step-by-step explanation:
lmk if you need an explanation :)
Answer:
Step-by-step explanation:
The first set of parentheses is unnecessary, so it can just be removed.
To remove the second set of parentheses, you must distribute the negative sign that is to its left. It changes every sign inside the parentheses.
Now you combine like terms.
Answer:
Step-by-step explanation:
The formula for determining the the area of a sector is expressed as
Area of Sector = θ/360 × πr²
Where
θ represents the central angle.
π is a constant whose value is 3.14
r represents the radius of the circle.
From the information given,
The central angle is π/7 radian. Converting to degrees, it becomes
π/7 × 180/π = 180/7 = 25.714 degrees.
Area of sector = 77 square meters
Therefore
77 = 25.714/360 × 3.14 × r²
77 = 0.2243r²
r² = 77/0.2243 = 343.29
r = √343.29 = 18.53 meters