document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=888285>Question 888285</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of the ages of a father and his son is 45 years. Five years ago, the product of their ages was 34. Find the age of the son and Father.\r<BR>\n" );
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document.write( "The sum of the present ages of the father and the son is 56 years. 4 years hence, the son’s age will be 1/3 that of the father. What are the present ages of the father and the son? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #537334 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=537334\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let f = father's age<BR>\n" );
document.write( "let s = son's age<BR>\n" );
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document.write( "Write an equation for each statement<BR>\n" );
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document.write( "The sum of the ages of a father and his son is 45 years.<BR>\n" );
document.write( "f + s = 45<BR>\n" );
document.write( "s = (45-f)<BR>\n" );
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document.write( " Five years ago, the product of their ages was 34.<BR>\n" );
document.write( "(f-5)*(s-5) = 34<BR>\n" );
document.write( "replace s with (45-f)<BR>\n" );
document.write( "(f-5)*(45-f-5) = 34<BR>\n" );
document.write( "(f-5)*(-f+40) = 34<BR>\n" );
document.write( "FOIL<BR>\n" );
document.write( "-f^2 + 40f + 5f - 200 - 34 = 0<BR>\n" );
document.write( "-f^2 + 45f - 234 = 0<BR>\n" );
document.write( "Multiply by -1<BR>\n" );
document.write( "f^2 - 45f + 234 = 0<BR>\n" );
document.write( "Factors to<BR>\n" );
document.write( "(f-39)(f-6) = 0<BR>\n" );
document.write( "Two solutions<BR>\n" );
document.write( "f = 39 yrs is fathers age, other solution unreasonable<BR>\n" );
document.write( "Find son's age<BR>\n" );
document.write( "s = 45 - 39<BR>\n" );
document.write( "s = 6 yrs is the son's age<BR>\n" );
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document.write( "Confirm this; 5 yrs ago, 34 * 1 = 34<BR>\n" );
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document.write( "The sum of the present ages of the father and the son is 56 years.<BR>\n" );
document.write( "f + s = 56<BR>\n" );
document.write( "f = (56 - s)<BR>\n" );
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document.write( "4 years hence, the son’s age will be 1/3 that of the father.<BR>\n" );
document.write( "s + 4 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F3 ALIGN=MIDDLE  ALT=\"1%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >(f + 4)<BR>\n" );
document.write( "multiply both sides by 3<BR>\n" );
document.write( "3(s + 4) = f + 4<BR>\n" );
document.write( "3s + 12 = f + 4<BR>\n" );
document.write( "3s = f + 4 - 12<BR>\n" );
document.write( "3s = f - 8<BR>\n" );
document.write( "replace f with (56-s)<BR>\n" );
document.write( "3s = 56 - s - 8<BR>\n" );
document.write( "3s + s = 48<BR>\n" );
document.write( "4s = 48<BR>\n" );
document.write( "s = 48/4<BR>\n" );
document.write( "s = 12 yrs is son's age<BR>\n" );
document.write( "I'll let you find father's age, check solution in given statements\r<BR>\n" );
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document.write( " What are the present ages of the father and the son? </SPAN>\n" );
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