document.write( "Question 703058: Please help me with this application problem: \r
\n" ); document.write( "\n" ); document.write( "Mary is three times as old as her son. in 12 years, Mary's age will be one year less than twice her sons age. How old is each now?
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Algebra.Com's Answer #433283 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "let Mary's age be \"x\" and her son's age \"y\"\r
\n" ); document.write( "\n" ); document.write( "given:\r
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\n" ); document.write( "\n" ); document.write( "Mary is three times as old as her son: \"x=3y\".......eq.1\r
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\n" ); document.write( "\n" ); document.write( "in \"12\" years, Mary's age will be \"one\" year \"less\" than \"twice\" her sons age:\r
\n" ); document.write( "\n" ); document.write( "\"x%2B12=2%28y%2B12%29-1\".......eq. 2\r
\n" ); document.write( "\n" ); document.write( "solve this system:\r
\n" ); document.write( "\n" ); document.write( "\"x=3y\".......eq.1
\n" ); document.write( "\"x%2B12=2%28y%2B12%29-1\".......eq. 2
\n" ); document.write( "_____________________________\r
\n" ); document.write( "\n" ); document.write( "\"x%2B12=2%28y%2B12%29-1\".......eq. 2...substitute \"x\" from eq. 1\r
\n" ); document.write( "\n" ); document.write( "\"3y%2B12=2%28y%2B12%29-1\"\r
\n" ); document.write( "\n" ); document.write( "\"3y%2B12=2y%2B24-1\"\r
\n" ); document.write( "\n" ); document.write( "\"3y-2y=24-12-1\"\r
\n" ); document.write( "\n" ); document.write( "\"y=11\".......son's age\r
\n" ); document.write( "\n" ); document.write( "and\r
\n" ); document.write( "\n" ); document.write( "\"x=3y\"
\n" ); document.write( "\"x=3%2A11\"
\n" ); document.write( "\"x=33\".......Mary's age \r
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