A small plane costs $700,000 new. Ten years later it is valued at
$250,000.
Assuming a linear depreciation, find the value of the plane when it is
6 years old and when it is 14 years old. (Hint: Write a model for the
situation first.)
I need to show all work. Thanks

Hello fredewq,

Value of aircraft new             = $700,000
Value of aircraft after ten years = $250,000

Aircraft has depreciated by         $450,000 in ten years.


Therefore linear depreciation = $45,000 per year.

Value of Aircraft at 6 years = $700,000 minus (6 x depreciation of $45,000)
                             = $430,000

Value of Aircraft at 14 years = $700,000 minus (14 x depreciation of $45,000)
                              = $70,000

hope this helps.

gan

Do you see how this problem is exactly the same as your water boiling
question?

In both questions you are given two points and asked to construct a
line through them and then evaluate the function at different points. 
Do you see the correlation between my answer and gan's?