document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=999205>Question 999205</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I put quotes to ask question for the parts I didn't understand. \r<BR>\n" );
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document.write( "Problem: At 9 P.M. an oil tanker traveling west in the ocean at 18 kilometers per hour passes the same spot as a luxury liner that arrived at the same spot at 8 P.M. while traveling north at 23 kilometers per hour. If the \"spot\" is represented by the origin, find the location of the oil tanker and the location of the luxury liner t hours after 8 P.M. Then find the distance D between the oil tanker and the luxury liner at that time. \r<BR>\n" );
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document.write( "D(t) =? \r<BR>\n" );
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document.write( "Soltn: \r<BR>\n" );
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document.write( "T=18(t-1) \"Why is it set up in this fashion, sure it's basic but I don't understand this set up\" \r<BR>\n" );
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document.write( "L=23t \r<BR>\n" );
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document.write( "T=18t-18 km west of the origin \r<BR>\n" );
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document.write( "L=23t km north of the origin \r<BR>\n" );
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document.write( "d=((18t-18)^2+(23t)^2)^(1/2) \"Why exactly are we using the distance formula here?\" \r<BR>\n" );
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document.write( "d=(324t^2-648t+324+529t^2)^(1/2) \r<BR>\n" );
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document.write( "d=(853t^2-648t+324)^(1/2) \r<BR>\n" );
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document.write( "dd/dt=(853t-324)/(853t^2-648t+324)^(1/2... \"Why was the derivative taken here? \r<BR>\n" );
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document.write( "dd/dt=0 only when 853t=324 \r<BR>\n" );
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document.write( "t=0.3798h \r<BR>\n" );
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document.write( "d(.3798)=14.175km \"Why was this plugged back into the original function? what does that cause?\" \r<BR>\n" );
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document.write( "Thank you for any and all help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #616898 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=616898\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "distance = speed * time\r<BR>\n" );
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document.write( "Tanker distance after tme t = 23 t\r<BR>\n" );
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document.write( "Tanker distance after time (t-1) = 18 (t-1)\r<BR>\n" );
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document.write( "Since they are travelling at right angles\r<BR>\n" );
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document.write( "apply Pythagoras theorem\r<BR>\n" );
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document.write( "Velocity is the change in position, so it's the slope of the position. \r<BR>\n" );
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document.write( " the slope of the position function, it is velocity.<BR>\n" );
document.write( "slope is dy/dx\r<BR>\n" );
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document.write( " </SPAN>\n" );
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