document.write( "Question 340358: a father is 39 years old and his son is 15 years old. after how many years the age of the father becomes 3 times the age of his son \n" ); document.write( "

Algebra.Com's Answer #243852 by Fombitz(32388) $\"\"$ $\"About$

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Let $\"X\"$ be the number of years until the father is 3 times the son's age,
\n" ); document.write( " $\"F=3S\"$
\n" ); document.write( " $\"%2839%2BX%29=3%2815%2BX%29\"$
\n" ); document.write( " $\"39%2BX=45%2B3X\"$
\n" ); document.write( " $\"2X=-6\"$
\n" ); document.write( " $\"X=-3\"$
\n" ); document.write( "It happened three years ago when the father was 36 and the son was 12.\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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