Question 1122489
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A candle is lit and burns and the length of the candle changes at a constant rate of -1.9 inches per hour. 
2 hours after the candle was lit the candle is 8.9 inches long. 


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a.  Write a formula that expresses the remaining length of the candle in inches, 
L, 
    in terms of the number of hours t that have elapsed since the candle was lit.


        The remaining length  L(t) = 8.9 + 2*1.9 - 1.9*t  inches,   t >= 0.   (1)



b.  Use your formula from part a. to determine how long the candle was before it was lit.


        how long the candle was before it was lit = L(0) = simply substitute t= 0 into the formula (1) to get = 8.9 + 2*1.9 inches.
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