document.write( "Question 935173: A man is older than his son by 30 years in how many years will the fathers age be twice his sons age? \n" ); document.write( "
Algebra.Com's Answer #568315 by ankor@dixie-net.com(22740)\"\" \"About 
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f = father's present age
\n" ); document.write( "s = son's
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\n" ); document.write( "I don't think we have enough information to get a unique solution, anyway
\n" ); document.write( " write an equation for each statement
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\n" ); document.write( "A man is older than his son by 30 years
\n" ); document.write( "f = s + 30
\n" ); document.write( " in how many years will the fathers age be twice his sons age?
\n" ); document.write( "let y = no. years for this to be true
\n" ); document.write( "f + y = 2(s+y)
\n" ); document.write( "f + y = 2s + 2y
\n" ); document.write( "f = 2s + 2y - y
\n" ); document.write( "f = 2s + y
\n" ); document.write( "Replace f with s+30
\n" ); document.write( "s + 30 = 2s + y
\n" ); document.write( "30 = 2s - s + y
\n" ); document.write( "30 = s + y
\n" ); document.write( "right here you can see there could be many solutions
\n" ); document.write( "If s = 20, y = 10, then f = 50
\n" ); document.write( "or
\n" ); document.write( "s = 10, y = 20, then f = 40
\n" ); document.write( "or
\n" ); document.write( "s = 5, y = 25, then f = 35\r
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