Suppose that the dollar value [tex]\( v(t) \)[/tex] of a certain house that is [tex]\( t \)[/tex] years old is given by the following exponential function:
[tex]\[ v(t) = 532,000(0.77)^t \][/tex]

1. Find the initial value of the house.
[tex]\[ \square \][/tex]

2. Does the function represent growth or decay?
A. growth
B. decay

3. By what percent does the value of the house change each year?
[tex]\[ \square \% \][/tex]



Answer :

Let's solve the problem step-by-step.

1. Initial Value of the House:

The initial value of an exponential function [tex]\( v(t) = v_0 \cdot b^t \)[/tex] is given by [tex]\( v_0 \)[/tex], which is the coefficient in front of the exponential term.

For the given function [tex]\( v(t) = 532,000 (0.77)^t \)[/tex], the initial value [tex]\( v_0 \)[/tex] is 532,000.

Therefore, the initial value of the house is
[tex]$ 532,000 $[/tex]

2. Determining if the Function Represents Growth or Decay:

In an exponential function of the form [tex]\( v(t) = v_0 \cdot b^t \)[/tex], if the base [tex]\( b \)[/tex] is less than 1, the function represents decay. If [tex]\( b \)[/tex] is greater than 1, the function represents growth.

Here, the base [tex]\( b \)[/tex] is 0.77, which is less than 1.

Therefore, the function represents
[tex]$ \text{decay} $[/tex]

3. Percent Change per Year:

The percent change per year in an exponential decay or growth function can be calculated as [tex]\((1 - b) \times 100\%\)[/tex], where [tex]\( b \)[/tex] is the base of the exponential.

For [tex]\( b = 0.77 \)[/tex], the percent change per year is:
[tex]$ (1 - 0.77) \times 100\% = 0.23 \times 100\% = 23\% $[/tex]

Therefore, the value of the house changes by
[tex]$ 23 \% $[/tex] per year.