document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=235375>Question 235375</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A truck driver traveled at 40 mph for the first part of a 646-mile trip, then increased his speed to 58 mph for the rest of the trip. The entire trip took 13 hours. How many hours are traveled at 58 mph?<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 #173395 by </B><A HREF=/tutors/aboutme.mpl?userid=Stitch><B>Stitch(470)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Stitch><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=173395\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The Setup<BR>\n" );
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document.write( "Equation 1: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2AX+%2B+58%2AY+=+646 ALIGN=MIDDLE  ALT=\"40%2AX+%2B+58%2AY+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation 2: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+%2B+Y+=+13 ALIGN=MIDDLE  ALT=\"X+%2B+Y+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Solution:<BR>\n" );
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document.write( "Solve equation 2 for one of the variables.  I picked X.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+%2B+Y+=+13 ALIGN=MIDDLE  ALT=\"X+%2B+Y+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" > Rewrite<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+=+13+-+Y ALIGN=MIDDLE  ALT=\"X+=+13+-+Y\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now plug (13 - Y) in for X in equation 1<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2AX+%2B+58%2AY+=+646 ALIGN=MIDDLE  ALT=\"40%2AX+%2B+58%2AY+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2A%2813+-+Y%29+%2B+58%2AY+=+646 ALIGN=MIDDLE  ALT=\"40%2A%2813+-+Y%29+%2B+58%2AY+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply the 40 by (13 - Y) and rewrite<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=520+-+40Y+%2B+58Y+=+646 ALIGN=MIDDLE  ALT=\"520+-+40Y+%2B+58Y+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine like terms<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=520+%2B+18Y+=+646 ALIGN=MIDDLE  ALT=\"520+%2B+18Y+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 520 from both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=18Y+=+126 ALIGN=MIDDLE  ALT=\"18Y+=+126\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by 18<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Y+=+7 ALIGN=MIDDLE  ALT=\"Y+=+7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now we know the the truck driver went 58mph for 7 hours.\r<BR>\n" );
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document.write( "Check Answer:<BR>\n" );
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document.write( "Plug 7 into equation 2 for Y<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+%2B+Y+=+13 ALIGN=MIDDLE  ALT=\"X+%2B+Y+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+%2B+7+=+13 ALIGN=MIDDLE  ALT=\"X+%2B+7+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 7 from both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+=+6 ALIGN=MIDDLE  ALT=\"X+=+6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now go back to equation 1 and plug 7 in for Y, and use 6 for X.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2AX+%2B+58%2AY+=+646 ALIGN=MIDDLE  ALT=\"40%2AX+%2B+58%2AY+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2A6+%2B+58%2A7+=+646 ALIGN=MIDDLE  ALT=\"40%2A6+%2B+58%2A7+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=240+%2B+406+=+646 ALIGN=MIDDLE  ALT=\"240+%2B+406+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=646+=+646 ALIGN=MIDDLE  ALT=\"646+=+646\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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