The resale value V, in thousands of dollars, of a boat is a function of the number of years t since the start of 2011, and the formula is
V = 12.5 − 1.3t.
(a) Calculate V(3).
(b) In what year will the resale value be 7.3 thousand dollars?
(c) Solve for t in the formula above to obtain a formula expressing t as a function of V.
(d) In what year will the resale value be 3.4 thousand dollars?

Respuesta :

Answer:

a) V(3) = 8.6.

b) The resale value will be 7.3 thousand dollars at the start of 2015.

c) [tex]t(V) = \frac{12.5 - V}{1.3}[/tex]

d) 2017

Step-by-step explanation:

We are given the following function:

[tex]V(t) = 12.5 - 1.3t[/tex]

(a) Calculate V(3).

This is V when t = 3. So

[tex]V(3) = 12.5 - 1.3(3) = 8.6[/tex]

So

V(3) = 8.6.

(b) In what year will the resale value be 7.3 thousand dollars?

t years after the start of 2011, and t is found when [tex]V(t) = 7.3[/tex]. So

[tex]V(t) = 12.5 - 1.3t[/tex]

[tex]7.3 = 12.5 - 1.3t[/tex]

[tex]1.3t = 5.2[/tex]

[tex]t = \frac{5.2}{1.3}[/tex]

[tex]t = 4[/tex]

2011 + 4 = 2015

The resale value will be 7.3 thousand dollars at the start of 2015.

(c) Solve for t in the formula above to obtain a formula expressing t as a function of V.

[tex]V(t) = 12.5 - 1.3t[/tex]

[tex]1.3t(V) = 12.5 - V[/tex]

[tex]t(V) = \frac{12.5 - V}{1.3}[/tex]

(d) In what year will the resale value be 3.4 thousand dollars?

t years after 2011, and t is found t when [tex]V = 3.4[/tex]. So

[tex]V(t) = 12.5 - 1.3t[/tex]

[tex]3.9 = 12.5 - 1.3t[/tex]

[tex]1.3t = 8.6[/tex]

[tex]t = \frac{8.6}{1.3}[/tex]

[tex]t = 6.62[/tex]

2011 + 6.62 = 2017

So the year is 2017.