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Question 995490:  A small business buys a computer for $4000. After 4 years the value of the computer is expected to be $200. For accounting purposes the business uses linear depreciation to assess the value of the computer at a given time. This means that if V is the value of the computer at time t, then a linear equation is used to relate V and t. 
(a) Find a linear equation that relates V (in dollars) and t (in yr).
 
 
 
(I keep getting confused on which comes first, v or t. Or how they relate to one another) 
 Answer by MathTherapy(10557)      (Show Source): 
You can  put this solution on YOUR website! A small business buys a computer for $4000. After 4 years the value of the computer is expected to be $200. For accounting purposes the business uses linear depreciation to assess the value of the computer at a given time. This means that if V is the value of the computer at time t, then a linear equation is used to relate V and t. 
(a) Find a linear equation that relates V (in dollars) and t (in yr).
 
(I keep getting confused on which comes first, v or t. Or how they relate to one another) 
V(t) signifies the value of the computer at a certain point in time (years) 
Since the value of the computer is $200 in the 4th year, we can determine the ANNUAL DEPRECIATION (D) by saying that: 
V(t) = 4,000 - Dt 
V(4) = 4,000 - D(4) ---- Substituting 4 for t, in years 
 200 = 4,000 - 4D ------ Substituting 200 for computer's value in the 4th year 
  4D = 4,000 - 200 
  4D = 3,800 
D, or annual depreciation  =  , or $950 
We now get the following equation:    
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