document.write( "Question 898106: A father is three times as old as the son .Nine year ago,the father was four times as old as the son find their age. \n" ); document.write( "

Algebra.Com's Answer #544543 by josgarithmetic(39617) $\"\"$ $\"About$

You can put this solution on YOUR website!
f and s\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"f=3s\"$
\n" ); document.write( "and
\n" ); document.write( " $\"f-9=4%28s-9%29\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"f-9=4s-36\"$
\n" ); document.write( " $\"f=4s-36%2B9\"$
\n" ); document.write( " $\"f=4s-27\"$
\n" ); document.write( "Substitute
\n" ); document.write( " $\"3s=4s-27\"$
\n" ); document.write( " $\"-s=-27\"$
\n" ); document.write( " $\"highlight%28s=27%29\"$
\n" ); document.write( "-
\n" ); document.write( " $\"f=3%2A27\"$
\n" ); document.write( " $\"highlight%28f=81%29\"$ \n" ); document.write( "

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