Algebra.Com's Answer #830020 by ikleyn(52780)![\"\"](\"/images/stars/stars-13.gif\")  
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document.write( "In 1982 the population density of a country was 64 people per square mile,
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document.write( "and in 2002 it was 82 people per square mile.
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document.write( "Use a linear function to estimate when the population density reached 89 people per square mile
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document.write( "In 20 years from 1982 to 2002, the average rate of increasing population density was\r\n" );
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document.write( " r =  =  = 0.9 of a person per square mile per year.\r\n" );
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document.write( "So, assuming that this rate remains constant, we write this linear equation for the future density\r\n" );
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document.write( " D = 82 + r*(t-2002).\r\n" );
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document.write( "To find a year when the density will reach 89 p/sq.mile, we write equation\r\n" );
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document.write( " 82 + 0.9*(t-2002) = 89,\r\n" );
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document.write( "and we find\r\n" );
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document.write( " t-2002 =  =  = 7.777...\r\n" );
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document.write( "It tells us that the density 89 p/sq.mile will be reached somewhen in the year 2009 or 2010\r\n" );
document.write( "depending on from which time moment in the year 2002 we started out our time counter (chronometer). ANSWER\r\n" );
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document.write( "Solved.\r
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