Milton has his money invested in a stock portfolio. The value, v(.r), of his
portfolio can be modeled with the function y(x) = 30,000(0.78)", where x is the
number of years since he made his investment. Which statement describes the rate
of change of the value of his portfolio?
A) It decreases 78% per year. B) It decreases 22% per year.
C) It increases 78% per year. D) It increases 22% per year.

B) It decreases 22% per year.

Step-by-step explanation:

We are given that The value, v(.r), of his  portfolio can be modeled with the function :

Where x is the number of years since he made his investment.

Formula :

Where P = Principal

r = rate of decrease

t = time

A = Amount after t years

So, On comparing

P = 30000

t=x

A=y(x)

So, r = 0.22

r=22%

So, Rate of decrease is 22%

So, Option B is true,

It decreases 22% per year.

problem:

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

f(5/2) = 10/3

i hope this !