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Suppose that an engineer determines that she can use the formula -t^2+14 less than or equal to P to estimate when the price
of carbon fibre will be P dollars per kilogram or less in t years from the present. when will the carbon fibre be available at $10/kg or less?
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To determine "t", you need to solve the equation
-t^2 + 14 = 10.
----->
-t^2 = 10 - 14,
-t^2 = -4,
t^2 = 4,
t = 2.
Answer. When ? - In two years from now.