Question 124751
After 8 months of use, the value of Kathy's computer had depreciated to $890. After 10 months, the value had gone down to $750. Assume that the value of the computer, V, is a linear function of the number of months of use, t.
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You have two points:
(8,890) and (10,750)
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a) Write an equation for the value of the computer after t months of use.
Slope = (750-890)/(10-8) = -140/2 = -70
Form is V=mt+b ; you have V, m, t, and can solve for "b".
750 = -70*10 + b
b = 1450
EQUATION:
V(t)=-70t + 1450
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b) How much did the computer cost originally?
V(0) = -70*0+1450 = 1450
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c) What was the monthly depreciation?
$70
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Cheers,
Stan H.