document.write( "Question 480860: The formula N=2x^2+4x+1 represents the number of households. N, in thousands, in a certain city that have a computer x years after 1990. According to the formula, in what year were there 97 thousand households with computers in this city? \n" ); document.write( "

Algebra.Com's Answer #329257 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "N=2x^2+4x+1 , where N, in thousands, have a computer x years after 1990. 
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document.write( "Solve in what year were there 97 thousand households with computers 
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document.write( " 97 = 2x^2 + 4x  1
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document.write( " 2x^2 + 4x - 96 = 0
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document.write( " x^2 + 2x - 48 = 0
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document.write( "factoring
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document.write( "(x+8)(x-6)= 0
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document.write( "   x = 6 |tossing out negative solution for number of years.
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document.write( " 1990 + 6 = 1996, the year there were 97 thousand households with computers \r
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document.write( " 2*6^2 + 4*6 + 1 = 72 + 24 + 1 = 97  |checking our answer \n" );
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