Answer:
Step-by-step explanation:
The function s(x)=0.9(.82)^x models the number of subscription in tens of thousands where x represents the number of years since the trend has been observed.
s(x) represents the number of subscriptions to the Dorchester Daily in a given year.
0.9 in ten thousands represents the initial number of subscriptions to the Dorchester Daily in a given year.
0.82 represents the rate at which the number of number of subscriptions to the Dorchester Daily is declining. The rate in percentage is 100 - 82 = 12% each year.
x represents the number of years since the trend has been observed.
Answer:
See explanation below to use the vertex form to solve a quadratic equation.
Step-by-step explanation:
(x - h)^2 - k = 0, the vertex is (h, -k)
An example below, taking a quadratic equation and completing the square:
x^2 - 2x - 1 = 0
x^2 - 2x = 1
(-2/-2)^2 = 1, add 1 to both sides of the equation.
x^2 - 2x + 1 = 1 + 1
(x - 1)^2 = 2
(x - 1)^2 - 2 = 0
The vertex is (1, -2)
3 subtracted from twice a number=2x-3
8 less than the number=x-8
2x-3=x-8
x=-5