math
posted by kennisha .
the population of Canadian city is modeled by P(t)= 12t^2 + 800t + 40,00, where t is the time in years. when t=0, the year is 2007
A) according to the model, what will the population be in 2020?
B)in what year is the population predicted to be 300,000?

so for 2020 , t = 13
P(13) = 12(13)^2 + 800(13) + 40000
= .....
for the population to be 300 000
300000=12t^2 + 800t + 40000
12t^2 + 800t  260000=0
3t^2 + 200t  65000=0
let's use the formula
t = (200 ± √820000)/6
= 117.6 years or a negative
totally unrealistic answer, but mathematically correct
the year would be 2007+117.6 = appr 2125 
hello hello
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