Answer:
5
Step-by-step explanation:
We are given the geometric series:
-1, - 2, - 4, - 8.......
In the geometric series above, the common ratio = second term/first term = -2/-1
= 2
Where common ratio is greater than 1(r >1)
The sum of a geometric progression =
Sn = a(rⁿ -1)/r - 1
In the question we are asked to find the number of term = n
Sn = -31
a = -1
r = 2
Hence,
-31 = -1(2ⁿ - 1)/2 - 1
-31 = -1(2ⁿ - 1)
-31 = -2ⁿ + 1
2ⁿ = 1 + 31
2ⁿ = 32
2ⁿ = 2^5
n = 5
Therefore, the number of terms(n) = 5
Answer:
y=-8
x=-23
Step-by-step explanation:
see attached document
Answer:
131
Step-by-step explanation:
Answer:
Height = 20 ; Base = 5
Step-by-step explanation:
Triangle Area = Base x Height x 1/2
50 = 1x × 4x × 1/2
50 = 4x^2 × 1/2
50 = 2x^2
25 = x^2
x=5
Height equals to 4x -> 4 × 5 = 20
Base equals to x -> 1 × 5 = 5
4(b - 6) + 19 # Starting equation
4b - 24 + 19 # Using the distributive property
4b - 5 # Simplified expression