The exponential decay graph shows the expected depreciation for a new boat, selling for $3500, over 10 years a. Write an exponential function for the graph.
b. Use the function in part a to find the value of the boat after 9.5 years.

Respuesta :

Answer:

(a) [tex]f(x)=3500(\frac{2}{\sqrt{7}})^x[/tex]

(b) $245.27

Explanation:

(a)

From the below graph it is clear that the graph it passes through the points (0,3500) and (2,2000).

The general form of an exponential function is

[tex]f(x)=ab^x[/tex]

where, a is the initial value and b is growth or decay factor.

Initial value is 3500, it means a=3500.

[tex]f(x)=3500b^x[/tex]

f(x)=2000 at x=2.

[tex]2000=3500b^2[/tex]

[tex]\frac{2000}{3500}=b^2[/tex]

[tex]\frac{4}{7}=b^2[/tex]

[tex]\sqrt{\frac{4}{7}}=b[/tex]

[tex]\frac{2}{\sqrt{7}}=b[/tex]

The exponential function for the graph is

[tex]f(x)=3500(\frac{2}{\sqrt{7}})^x[/tex]

(b)

We need to find the value of the boat after 9.5 years.

Substitute x=9.5 in the above function.

[tex]f(9.5)=3500(\frac{2}{\sqrt{7}})^{9.5}[/tex]

[tex]f(9.5)=245.26598[/tex]

[tex]f(9.5)\approx 245.27[/tex]

Therefore, the value of the boat after 9.5 years is $245.27.

Ver imagen erinna

A. y=3500(2/√7)^x

B. y=$245.27