document.write( "Question 333745: My algebra teacher gave us this problem, I don't know how to start solving it. Please help me.
\n" ); document.write( "Marty is 1/3 as old as her mother. Five years ago she was only 1/5 of the age of her mother. How old is Marty? \n" ); document.write( "

Algebra.Com's Answer #239163 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!
My algebra teacher gave us this problem, I don't know how to start solving it. Please help me.
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document.write( "Let X = Marty's age now\r\n" );
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document.write( "Let Y = Mother's age now\r\n" );
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document.write( "Then \r\n" );
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document.write( "Marty's age five years age = (X-5)\r\n" );
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document.write( "Mother's age five years ago = (Y-5)\r\n" );
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document.write( "1/3 of Mother's age now = \r\n" );
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document.write( "1/5 of Mother's age five years ago = \r\n" );
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\n" ); document.write( ">>...Marty is 1/3 as old as her mother.
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document.write( "Marty's age = 1/3 of Mother's age now\r\n" );
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document.write( "     X      =              \r\n" );
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\n" ); document.write( ">>...Five years ago she (Marty) was only 1/5 of the age of her mother...<<
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document.write( "Marty's age five years ago = 1/5 of Mother's age five years ago \r\n" );
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document.write( "         (X-5)             =     \r\n" );
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document.write( "     \r\n" );
document.write( "So we have these two equations \r\n" );
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document.write( "Multiply both sides of the first equation by 3 to clear of fractions.\r\n" );
document.write( "Multiply both sides of the first equation by 5 to clear of fractions.\r\n" );
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document.write( "Canceling clears fractions:\r\n" );
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document.write( "Simplifying further:\r\n" );
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document.write( "Simplifying further:\r\n" );
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document.write( "Since the first equations tells us that Y = 3X we can replace the Y\r\n" );
document.write( "in the second equation \r\n" );
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document.write( "by 3X\r\n" );
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document.write( "So Marty is 10 years old.  However we need to find her\r\n" );
document.write( "Mothers age so we can check.  We use\r\n" );
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document.write( "Y = 3X\r\n" );
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document.write( "Y = 3(10)\r\n" );
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document.write( "Y = 30\r\n" );
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document.write( "So her mother is 30.\r\n" );
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document.write( "Let's check:\r\n" );
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document.write( "Marty is 1/3 as old as her mother.\r\n" );
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document.write( "Indeed 10 is 1/3 of 30\r\n" );
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document.write( "Five years ago she was only 1/5 of the age of her mother\r\n" );
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document.write( "Five years ago se was 5 and he mother was 25, and indeed\r\n" );
document.write( "5 is 1/5 of 25.\r\n" );
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document.write( "So we know we are right.\r\n" );
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document.write( "Edwin

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