document.write( "Question 307124: Glenn is 24 years old. Glenn is twice as old as Jeni was when Glenn was as old as Jeni is now. How old is Jeni? \n" ); document.write( "
Algebra.Com's Answer #219721 by Edwin McCravy(20060)\"\" \"About 
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document.write( "Let Jeni be J years old now.\r\n" );
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\n" ); document.write( "Glenn is 24 years old. Glenn is twice as old as Jeni was...
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document.write( "Stop right there.  Let that \"was\" be x years ago.  So x years ago, \r\n" );
document.write( "Jeni was 12.  Therefore J-x = 12\r\n" );
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document.write( "Also x years ago Glenn was 24-x \r\n" );
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document.write( "But x years ago was also...  \r\n" );
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\n" ); document.write( "...when Glenn was as old as Jeni is now.
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document.write( "So Glenn's age then, which was 24-x, is equal to J,\r\n" );
document.write( "which is Jeni's age now.\r\n" );
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document.write( "So we have this system of two equations in two unknowns:\r\n" );
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document.write( "\"system%28J-x=12%2C24-x=J%29\"\r\n" );
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document.write( "Solve that and get x=6 and J=18.\r\n" );
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document.write( "So Jeni is 18.\r\n" );
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document.write( "Checking, 6 years ago Glenn was 18, Jeni's age now. And\r\n" );
document.write( "6 years ago Jeni was 12, and Glenn's age now, 24, is twice\r\n" );
document.write( "12, Jeni's age then.\r\n" );
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document.write( "Edwin

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