document.write( "Question 1145713: The sum of Sam and Mary's age is 60. Twelve years ago, Sam was three times as old as Mary.\r
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Algebra.Com's Answer #766974 by MathTherapy(10552)\"\" \"About 
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\n" ); document.write( "The sum of Sam and Mary's age is 60. Twelve years ago, Sam was three times as old as Mary.\r
\n" ); document.write( "\n" ); document.write( "1. Write a system of equations to represent this situation.\r
\n" ); document.write( "\n" ); document.write( "2. Find Mary's age now
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Let Sam's and Mary's ages be S and M, respectively
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document.write( "Then equation 1 is: S + M = 60
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document.write( "Equation 2: S - 12 = 3(M - 12)____S - 12 = 3M - 36_____S - 3M = - 24
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document.write( "S + M = 60 ----- eq (i)
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document.write( "S - 3M = - 24 ---- eq (ii)
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document.write( "4M = 84 ----- Subtracting eq (ii) from eq (i)
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document.write( "M, or Mary is: \"highlight_green%28matrix%281%2C4%2C+84%2F4%2C+%22=%22%2C+21%2C+years-old%29%29\"
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document.write( "That's it!! Nothing COMPLEX or CONFUSING! \n" );
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