document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=139180>Question 139180</A>: <I><SPAN STYLE=\"word-break: break-all;\"> kindly help me with this other problem. PLEASE\r<BR>\n" );
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document.write( "A father is 20 years older than his son. In 4 years time he will be twice as old as his son. Determine their present ages. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #101500 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=101500\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> write an equation for each statement:<BR>\n" );
document.write( ":A father is 20 years older than his son.\"<BR>\n" );
document.write( "f = s + 20<BR>\n" );
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document.write( "\" In 4 years time he will be twice as old as his son.\"<BR>\n" );
document.write( "f + 4 = 2(s+4)<BR>\n" );
document.write( "f = 4 = 2s + 8<BR>\n" );
document.write( "f = 2s + 8 - 4<BR>\n" );
document.write( "f = 2s +4<BR>\n" );
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document.write( "Determine their present ages.<BR>\n" );
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document.write( "Substitute (s+20) for f in the above equation, (from the 1st equation); find s:<BR>\n" );
document.write( "s + 20 = 2s + 4<BR>\n" );
document.write( "20 - 4 = 2s - s<BR>\n" );
document.write( "16 = s<BR>\n" );
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document.write( "The son is 16 and the father is (16+20) = 36<BR>\n" );
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document.write( ":\r<BR>\n" );
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document.write( "Check solution in the statement:<BR>\n" );
document.write( "\"In 4 years time he will be twice as old as his son. \"<BR>\n" );
document.write( "36 + 4 = 2(16 + 4); confirms our solution  </SPAN>\n" );
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