document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=843147>Question 843147</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a father is four times as old as his son. in 8 years he will be 3 times as old. how old will his son be </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #507973 by </B><A HREF=/tutors/aboutme.mpl?userid=LinnW><B>LinnW(1048)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=LinnW><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=LinnW><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=507973\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> set s = son's age , f = father's age<BR>\n" );
document.write( "f = 4s<BR>\n" );
document.write( "f+8 = 3(s+8)<BR>\n" );
document.write( "substitute 4s for f<BR>\n" );
document.write( "4s + 8 = 3s + 24<BR>\n" );
document.write( "add -3s to each side<BR>\n" );
document.write( "s + 8 = 24<BR>\n" );
document.write( "add -8 to each side<BR>\n" );
document.write( "s = 16<BR>\n" );
document.write( "so f = 4*16 = 64<BR>\n" );
document.write( "Let's verify f+8 = 3(s+8)<BR>\n" );
document.write( "64+8 =? 3(16+8)<BR>\n" );
document.write( "72 =? 3(24)<BR>\n" );
document.write( "72 = 71<BR>\n" );
document.write( "So we know the son's age is 16 and the father is 64<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );