document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=80653>Question 80653</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 3.	Steve traveled 600 miles at a certain speed. Had he gone 20mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle.\r<BR>\n" );
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document.write( "y=time<BR>\n" );
document.write( "xy=600<BR>\n" );
document.write( "(x+20)(y-1)=600\r<BR>\n" );
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document.write( "Now what do I do? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #57867 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=57867\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Steve traveled 600 miles at a certain speed. Had he gone 20mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle.<BR>\n" );
document.write( "y=time<BR>\n" );
document.write( "xy=600<BR>\n" );
document.write( "(x+20)(y-1)=600<BR>\n" );
document.write( "Now what do I do?<BR>\n" );
document.write( ":<BR>\n" );
document.write( "I would do it this way:<BR>\n" );
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document.write( "Let x = original speed<BR>\n" );
document.write( "Then (x+20) = faster speed (as you had)<BR>\n" );
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document.write( "Write a time equation: Time = dist/speed<BR>\n" );
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document.write( "Original time - 1 = Faster time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28600%2Fx%29 ALIGN=MIDDLE  ALT=\"%28600%2Fx%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > - 1 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=600%2F%28x%2B20%29 ALIGN=MIDDLE  ALT=\"600%2F%28x%2B20%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Multiply equation by x(x+20) and you have:<BR>\n" );
document.write( "600(x+20) - x(x+20) = 600x<BR>\n" );
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document.write( "600x + 12000 - x^2 - 20x = 600x<BR>\n" );
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document.write( "-x^2 - 20x + 600x - 600x + 12000 = 0<BR>\n" );
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document.write( "-x^2 - 20x + 12000 = 0<BR>\n" );
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document.write( "x^2 + 20x - 120000 = 0: multiplied equation by 0 (easier to factor)<BR>\n" );
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document.write( "Factors to:<BR>\n" );
document.write( "(x+120)(x-100) = 0<BR>\n" );
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document.write( "x = +100, the positive solution is what we want here<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "600/100 - 1 = 600/120; proves our solution<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );