<PRE><B>Question 190783</B>
Suppose that N = sqrt (x + 4) models the number of cases of an infection, in millions of a disease x years from now. 
Approx. how many cases of the infection will there be 16 years from now? 
N(16) = sqrt(16+4) = sqrt(20 = 2sqrt(5) is appox. 4.47214 million
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In approx. how many years will there be 6 million cases?
6 = sqrt(x+4)
36 = x+4
x = 32 years
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Cheers,
Stan H.
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