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| Question 1071699:  When you are 18 years old you have a hair that is 19 centimeters, and your hair grows about 12 centimeters each year. Let H(t) be the length, in centimeters, of that hair t years after age 18.
 a) fine a formula that gives H as a linear function of t
 b) how long will it take for the air to reach a length of 92 centimeters.
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website!  When you are 18 years old you have a hair that is 19 centimeters, and your hair grows about 12 centimeters each year. Let H(t) be the length, in centimeters, of that hair t years after age 18. H(18) = 19
 m = 12
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 Form:: H(t) = m*t + b
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 Solve for "b"::
 19 = 12*18 + b
 b = -197
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 a) fine a formula that gives H as a linear function of t
 H(t) = 12t - 197
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 b) how long will it take for the air to reach a length of 92 centimeters.
 Solve::
 92 = 12t - 197
 12t = 289
 time = 24 (age at which hair length is 92 cm
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 Cheers,
 Stan H.
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