document.write( "Question 846191: Five years from now, a father's age will be three times his son's age, and five years ago, he was seven times as old as his son was. How do I set up this problem to solve as a system? \n" ); document.write( "
Algebra.Com's Answer #509666 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Let f = father's age
\n" ); document.write( "let s = son's age
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\n" ); document.write( "Write an equation for each statement, smplify.
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\n" ); document.write( "\"Five years from now, a father's age will be three times his son's age,\"
\n" ); document.write( "f + 5 = 3(s+5)
\n" ); document.write( "f + 5 = 3s + 15
\n" ); document.write( "f = 3s + 15 - 5
\n" ); document.write( "f = 3s + 10
\n" ); document.write( "\"and five years ago, he was seven times as old as his son was.\"
\n" ); document.write( "f - 5 = 7(s-5)
\n" ); document.write( "f - 5 = 7s - 35
\n" ); document.write( "f = 7s - 35 + 5
\n" ); document.write( "f = 7s - 30
\n" ); document.write( "Use this to replace f in the 1st equation
\n" ); document.write( "7s - 30 = 3s + 10
\n" ); document.write( "You should be able to solve this now. Check your solutions in both statements\r
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\n" ); document.write( "\n" ); document.write( " How do I set up this problem to solve as a system? \n" ); document.write( "
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