document.write( "Question 167751This question is from textbook
\n" ); document.write( ": I am working on equations with absolute value and I need help with this word problem, please.\r
\n" ); document.write( "\n" ); document.write( "The problem reads:\r
\n" ); document.write( "\n" ); document.write( "The number of U.S. teenagers in the age category \"15-19-years olds\" during any year between 1980 and 1998 can be modeled approximately by \r
\n" ); document.write( "\n" ); document.write( "T=332/x-11.5/+17000\r
\n" ); document.write( "\n" ); document.write( "where T is the number of \"15-19-years-olds\" in thousands and x is the number of years since January 1, 1980 (U.S. Census Bureau, Current Poplulatioin Reports.) Use the model to determine the year in which the number of 15-19-year olds in the U.S. was 18,700,000 (18,700 thousands).\r
\n" ); document.write( "\n" ); document.write( "The book comes up with the answer of 1986 and 1996, I cant even come close to them years....please help. Thanks
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Algebra.Com's Answer #123660 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"332%2Aabs%28x-11%29%2B17000=18700\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"332%2Aabs%28x-11%29=1700\" Subtract 17,000 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"abs%28x-11%29=5.12048\" Divide both sides by 332 (this is an approximate value)\r
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\n" ); document.write( "\n" ); document.write( "Break up the absolute value (remember, if you have \"abs%28x%29=a\", then \"x=-a\" or \"x=a\")\r
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\n" ); document.write( "\n" ); document.write( "\"x-11=-5.12048\" or \"x-11=5.12048\" Set the expression \"x-11\" equal to the original value 5.12048 and it's opposite -5.12048\r
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\n" ); document.write( "\n" ); document.write( "Now lets focus on the first equation \"x-11=-5.12048\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-5.12048%2B11\"Add 11 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=5.87952\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "So rounding to the nearest whole number, we get \"x=6\"\r
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\n" ); document.write( "\n" ); document.write( "This means that 6 years from the beginning (which is 1980), the population of 15-19 yr olds was 18,700,000. \r
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\n" ); document.write( "\n" ); document.write( "So in 1986 (which is 6 years away from 1980), the population of 15-19 yr olds was 18,700,000.\r
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\n" ); document.write( "\n" ); document.write( "Now lets focus on the second equation \"x-11=5.12048\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=5.12048%2B11\"Add 11 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=16.12048\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "So rounding to the nearest whole number, we get \"x=16\"\r
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\n" ); document.write( "\n" ); document.write( "This means that 16 years from the beginning (which is 1980), the population of 15-19 yr olds was 18,700,000. \r
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\n" ); document.write( "\n" ); document.write( "So in 1996 (which is 16 years away from 1980), the population of 15-19 yr olds was 18,700,000.\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So we got the solutions (after rounding to the nearest whole number) \"x=6\" and \"x=16\". These solutions represented the number of years after 1980. \r
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\n" ); document.write( "\n" ); document.write( "So in 1986 and in 1996 the population of 15-19 year olds was 18,700,000
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