document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1204835>Question 1204835</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of age's of a man and his daughter is 120years.six years ago,the man's age was thrice that of his daughter.find their present age.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #841344 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=841344\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "A typical formal algebraic solution would start with the given information that the sum of the man's age and his daughter's age is 120:<br><BR>\n" );
document.write( "m = man's age<BR>\n" );
document.write( "d = daughter's age<BR>\n" );
document.write( "m+d=120<br><BR>\n" );
document.write( "Then the next step would be to write the equation that says six years ago the man was three times as old as his daughter:<br><BR>\n" );
document.write( "m-6 = man's age 6 years ago<BR>\n" );
document.write( "d-6 = daughter's age 6 years ago<BR>\n" );
document.write( "m-6=3(d-6)<br><BR>\n" );
document.write( "From there some method would be used to solve the system of two equations in m and d to find their current ages.<br><BR>\n" );
document.write( "I leave it to you to follow through with that solution method if you want; it is good algebra practice.<br><BR>\n" );
document.write( "But a different setup for solving the problem, using a single variable, makes solving the problem easier.<br><BR>\n" );
document.write( "Instead of starting with the first piece of given information, start with the second.  6 years ago, the man was three times as old as his daughter:<br><BR>\n" );
document.write( "x = daughter's age 6 years ago<BR>\n" );
document.write( "3x = man's age 6 years ago<br><BR>\n" );
document.write( "The sum of their ages now is 120:<br><BR>\n" );
document.write( "x+6 = daughter's age now<BR>\n" );
document.write( "3x+6 = man's age now<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2B6%29%2B%283x%2B6%29=120 ALIGN=MIDDLE  ALT=\"%28x%2B6%29%2B%283x%2B6%29=120\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B12=120 ALIGN=MIDDLE  ALT=\"4x%2B12=120\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x=108 ALIGN=MIDDLE  ALT=\"4x=108\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=27 ALIGN=MIDDLE  ALT=\"x=27\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "ANSWERS: Their ages now are<BR>\n" );
document.write( "daughter: x+6 = 27+6 = 33<BR>\n" );
document.write( "man: 3x+6 = 81+6 = 87<br><BR>\n" );
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