document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=52258>Question 52258</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What am I doing wrong? How would you set this up as an equation?\r<BR>\n" );
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document.write( "The Michigan plant of DynoTech Industries is four times as old as the Ohio plant. If the difference in the ages of the two plants is 9 years, what is the age of each?\r<BR>\n" );
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document.write( "x+4x=y-9\r<BR>\n" );
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document.write( "I didn't bring my text book, but I'll find out if I have another problem.<BR>\n" );
document.write( "Thank You </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #34810 by </B><A HREF=/tutors/aboutme.mpl?userid=rchill><B>rchill(405)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rchill><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=34810\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You've got a good start, but don't introduce a 2nd variable here.  You've got x as the Michigan plant -- good; and 4x is the age of the Ohio plant -- very good.  The difference in their ages is 9; that means that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x-x=9 ALIGN=MIDDLE  ALT=\"4x-x=9\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Solving for x, we get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x=9 ALIGN=MIDDLE  ALT=\"3x=9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, which simplifies to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=3 ALIGN=MIDDLE  ALT=\"x=3\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  That means the Michigan plant is 3 years old and the Ohio plant is 4 times that, or 12 years old.  Note the difference in ages is 9. </SPAN>\n" );
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