First, we need to solve for the common ratio from the data given by using the equation.
a(n) = a(1) r^(n-1)
15 = -3 r^(2-1)
-5 = r
r = -5
Then, we can find the sum by the expression:
S(n) = a(1) ( 1 - r^n) / 1-r
S(8) = -3 (1 + 5^8) / 1+5
S(8) = -195313
Answer:
42.25 feet
Step-by-step explanation:
The height function is a parabola. The maximum value of a negative parabola is at the vertex, which can be found with:
x = -b/2a
where a and b are the coefficients in y = ax² + bx + c.
Here, we have y = -16t² + 52t. So a = -16 and b = 52. The vertex is at:
t = -52 / (2×-16)
t = 13/8
Evaluating the function:
h(13/8) = -16(13/8)² + 52(13/8)
h(13/8) = -169/4 + 169/2
h(13/8) = 169/4
h(13/8) = 42.25
The answer is 3 because z to the y a-1
7 out of 12 have 31 im guessing
