document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=486052>Question 486052</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boardwalk is parallel to and 210 ft inland from a straight shoreline. A sandy beach lies between the boardwalk and the shoreline. A man is standing on the boardwalk, exactly 750 ft across the sand from his beach umbrella, which is right at the shoreline. The man walks 4ft/s on the boardwalk and 2 ft/s on the sand. How far should he walk on the boardwalk before veering off onto the sand if he wishes to reach his umbrella in exactly 4 min 45 s? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #332391 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=332391\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> : A boardwalk is parallel to and 210 ft inland from a straight shoreline.<BR>\n" );
document.write( " A sandy beach lies between the boardwalk and the shoreline.<BR>\n" );
document.write( " A man is standing on the boardwalk, exactly 750 ft across the sand from his beach umbrella, which is right at the shoreline.<BR>\n" );
document.write( " The man walks 4ft/s on the boardwalk and 2 ft/s on the sand.<BR>\n" );
document.write( "How far should he walk on the boardwalk before veering off onto the sand if he wishes to reach his umbrella in exactly 4 min 45 s?<BR>\n" );
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document.write( "Change 4 min 45 sec to 285 sec<BR>\n" );
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document.write( "Find the distance from the man to a point (p) on the boardwalk directly opposite the umbrella.<BR>\n" );
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document.write( "p = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28720%5E2+-+210%5E2%29 ALIGN=MIDDLE  ALT=\"sqrt%28720%5E2+-+210%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "p = 720 ft <BR>\n" );
document.write( ";<BR>\n" );
document.write( "Let x = the dist the man will walk on the boardwalk, before onto the sand<BR>\n" );
document.write( "The distance walked on the sand will be the hypotenuse of a triangle with the legs of 210' and (720-x) or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28210%5E2+%2B+%28720-x%29%5E2%29 ALIGN=MIDDLE  ALT=\"sqrt%28210%5E2+%2B+%28720-x%29%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write the time equation<BR>\n" );
document.write( "b.w. time + sand walk time = 285 sec<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2F4 ALIGN=MIDDLE  ALT=\"x%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28sqrt%28210%5E2+%2B+%28720-x%29%5E2%29%29%2F2 ALIGN=MIDDLE  ALT=\"%28sqrt%28210%5E2+%2B+%28720-x%29%5E2%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 285<BR>\n" );
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document.write( "Get rid of the denominators, mult by 4, results<BR>\n" );
document.write( "x + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2Asqrt%28210%5E2+%2B+%28720-x%29%5E2%29 ALIGN=MIDDLE  ALT=\"2%2Asqrt%28210%5E2+%2B+%28720-x%29%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1140<BR>\n" );
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document.write( "After a lot math obtained a quadratic equation of:<BR>\n" );
document.write( "3s^2 - 3480x + 950400 = 0<BR>\n" );
document.write( "Two solutions<BR>\n" );
document.write( "x = 720<BR>\n" );
document.write( "x = 440 ft. the reasonable solution is the distance he walked on the boardwalk<BR>\n" );
document.write( " </SPAN>\n" );
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