document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=102852>Question 102852</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dorothy drives 10 kilometers, then increases her speed by 10 kilometers per hour and drives another 25 kilometers. Find her original speed if she drove for 45 minutes.\r<BR>\n" );
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document.write( "Please help me with this!! Thanks!! I can't understand how to answer this!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #74804 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=74804\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> time=distance/rate ... let x=speed ... 45/60=.75\r<BR>\n" );
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document.write( "(10/x)+(25/(x+10))=.75 ... 10(x+10)+25(x)=.75(x)(x+10) ... 40x+400+100x=3x^2+30x\r<BR>\n" );
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document.write( "3x^2-110x-400=0 ... (3x+10)(x-40)=0 ... x=-10/3 and x=40 ... negative value not realistic </SPAN>\n" );
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