document.write( "Question 383508: I am stuck on this question. The formula f(x)=2x^2+22x+320 models the number of inmates(in thousands) in US State and federal prisons x years after 1980.
\n" ); document.write( "A) In which year were there 740 thousand inmates in US state and federal prisons? I started with adding 740 to the 320 and then broke it down and if I am right i got 2(x^2+11+530). But not sure where to go from here.\r
\n" ); document.write( "\n" ); document.write( "B) In which year where there 1100 thousand inmates in US state and federal prisons?
\n" ); document.write( "This is in review for my finals. Any help is great
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Algebra.Com's Answer #271564 by Edwin McCravy(20064) $\"\"$ $\"About$

You can put this solution on YOUR website!
I am stuck on this question. The formula $\"%22f%28x%29%22=2x%5E2%2B22x%2B320\"$ models the number of inmates(in thousands) in US State and federal prisons x years after 1980.
\n" ); document.write( "A) In which year were there 740 thousand inmates in US state and federal prisons?
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document.write( "x = the number of years after 1980.\r\n" );
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document.write( "f(x) = the number of thoiusands of inmates in the year which is x years after 1980\r\n" );
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\n" ); document.write( "A) In which year were there 740 thousand inmates in US state and federal prisons?
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document.write( "x = the number of years after 1980 = ?  (That's what we want to find)\r\n" );
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document.write( "f(x) = the number of inmates in the year which is x years after 1980 = 740  (That is given)\r\n" );
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document.write( "So we substitute 740 for f(x) in \r\n" );
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document.write( "Can you solve that? If not post again asking how.\r\n" );
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document.write( "Solutions are x = 10 and x = -21\r\n" );
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document.write( "We ignore the negative value and our final answer is\r\n" );
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document.write( "10 years after 1980, or the year 1990.\r\n" );
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\n" ); document.write( "B) In which year where there 1100 thousand inmates in US state and federal prisons?
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\r\n" );
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document.write( "x = the number of years after 1980 = ? (That's what we want to find)\r\n" );
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document.write( "f(x) = the number of inmates in the year which is x years after 1980 = 1100  (That is given)\r\n" );
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document.write( "So we substitute 1100 for f(x) in \r\n" );
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document.write( "Can you solve that? If not post again asking how.\r\n" );
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document.write( "Solutions are x = 15 and x = -26\r\n" );
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document.write( "We ignore the negative value and our final answer is\r\n" );
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document.write( "15 years after 1980, or the year 1995.\r\n" );
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document.write( "Edwin

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