SOLUTION: a new television depreciates $120 per year, and it is worth $340 after four years. find a function that describes the value of this television, if x is the age of the television in

Algebra ->  Equations -> SOLUTION: a new television depreciates $120 per year, and it is worth $340 after four years. find a function that describes the value of this television, if x is the age of the television in      Log On


   

Question 186634This question is from textbook mathematical analysis
: a new television depreciates $120 per year, and it is worth $340 after four years. find a function that describes the value of this television, if x is the age of the television in years.
In full details please, thank you This question is from textbook mathematical analysis

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let y = the original value of the TV
given:
120 = depreciation/1 year
You have to understand that depreciation
is what the TV loses in value each year,
so every year it's worth less, and then it
gets depreciated again
------------------------------------------
y+-+120 is the value of the TV after 1 year
y+-+120+-+120 is the value of the TV after 2 years
y+-+120+-+120+-+120 is the value of the TV after 3 years
y+-+4%2A120 is the value of the TV after 4 years
The problem says the TV is worth $340 after 4 years, so
y+-+4%2A120+=+340
y+=+340+%2B+480
y+=+820
So, the TV was originally worth $820
------------------------------------
Now I need to write a function that tells me the
value of the TV for any given year
If x is the year after purchase,
and V%28x%29 is the value of the TV that year
V%28x%29+=+820+-+120x
A quick check is:
What is the TV worth after 4 years?
V%28x%29+=+820+-+120x
V%284%29+=+820+-+480
V%284%29+=+340
That's what it should be