document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=683891>Question 683891</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat sails 30 miles to the east from a point P, then it changes direction and sails to the south. If this boat is sailing at a constant speed of 10 miles/hr, at what rate is its distance from the point P increasing \r<BR>\n" );
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document.write( "a)	2 hours after it leaves the point P <BR>\n" );
document.write( "b)	7 hours after it leaves the point P </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #423859 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=423859\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The route taken by the boat is a right angle<BR>\n" );
document.write( "so the actual distance from starting point is any point of the hypotenuse\r<BR>\n" );
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document.write( "d(east)= 30 mi<BR>\n" );
document.write( "d(south)=10 mi/h<BR>\n" );
document.write( "After2 hours it would be 20 miles down south\r<BR>\n" );
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document.write( "distance from origin = sqrt(30^2+20^2)  ( the legs of the right triangle)\r<BR>\n" );
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document.write( "After 2 hours it is sqrt(1300) from the origin\r<BR>\n" );
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document.write( "its rate with respect to origin = d/t<BR>\n" );
document.write( "sqrt(1300)/2\r<BR>\n" );
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document.write( "10sqrt(13)/2<BR>\n" );
document.write( "5sqrt(13) mi/h is the rate with respect to origin P after 5 hours. </SPAN>\n" );
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