document.write( "Question 1150389: Twelve years ago my father was twice as old as I was, and three years ago our combined age was 108. How old is my father now? \n" ); document.write( "
Algebra.Com's Answer #771778 by ankor@dixie-net.com(22740)\"\" \"About 
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let f = father's present age
\n" ); document.write( "let y = your present age
\n" ); document.write( ":
\n" ); document.write( "Write an equation for each statement, simplify each equation
\n" ); document.write( ":
\n" ); document.write( "Twelve years ago my father was twice as old as I was,
\n" ); document.write( "f - 12 = 2(y-12)
\n" ); document.write( "f - 12 = 2y - 24
\n" ); document.write( "f = 2y - 24 + 12
\n" ); document.write( "f = 2y - 12\r
\n" ); document.write( "\n" ); document.write( " and three years ago our combined age was 108.
\n" ); document.write( "(f-3) + (y-3) = 108
\n" ); document.write( "f + y - 6 = 108
\n" ); document.write( "f + y = 108 + 6
\n" ); document.write( "f + y = 114
\n" ); document.write( "Replace f with (2y-12) from the 1st equation
\n" ); document.write( "(2y-12) + y = 114
\n" ); document.write( "3y = 114 + 12
\n" ); document.write( "3y = 126
\n" ); document.write( "y = 126/3
\n" ); document.write( "y = 42 is your age
\n" ); document.write( "then
\n" ); document.write( "f = 2(42) - 12
\n" ); document.write( "f = 84 - 12
\n" ); document.write( "f = 72 is father's age
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Confirm that in statement:
\n" ); document.write( "\"twelve years ago my father was twice as old as I was,\"
\n" ); document.write( "72 - 12 = 2(42-12)
\n" ); document.write( "60 = 2(30) \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
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