document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1139602>Question 1139602</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The Gateway Arch in a city has the shape of a catenary (a U-shaped curve similar to a parabola). It can be approximated by the following model, where x and y are measured in feet.<BR>\n" );
document.write( "y = -(3/1000)(x + 400)(x - 400). How high is the arch? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #760089 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=760089\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y = -(3/1000)(x + 400)(x - 400). How high is the arch? <BR>\n" );
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document.write( "That is a parabola.<BR>\n" );
document.write( "y = (-3/1000)*(x^2 - 160000)<BR>\n" );
document.write( "With no x term, the vertex is at x = 0<BR>\n" );
document.write( "y = (-3/1000)*(-160000)<BR>\n" );
document.write( "y = 480 feet<BR>\n" );
document.write( " </SPAN>\n" );
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