Question 105730
Given that the value of a car (V) that is t years old is given by the equation:
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V = -2000t + 21,000 
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The problem tells you that the value of a car is $11,000 and asks you how many years old
the car is ... where t is the age of the car. Substitute 11000 for V in the equation to
get:
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11000 = -2000t + 21000
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Get rid of the 21000 on the right side by subtracting 21000 from both sides to change the
equation to:
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-10000 = -2000t
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Now solve for t by dividing both sides of this equation by -2000 and you have:
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-10000/-2000 = t
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Doing the division on the left side results in:
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5 = t
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The car is 5 years old.
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Hope this helps you to understand this problem and how to find the answer.
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