document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1160972>Question 1160972</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A bridge is built in the shape of a parabolic arch. The bridge has a span of 180 feet and a maximum height of 40 feet above the water at the center. Can a sailboat that is 39 feet tall fit under the bridge 10 feet from the​ center? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #784385 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=784385\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A bridge is built in the shape of a parabolic arch. The bridge has a span of 180 feet and a maximum height of 40 feet above the water at the center. Can a sailboat that is 39 feet tall fit under the bridge 10 feet from the​ center?<BR>\n" );
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document.write( "Find the equation of the parabola.<BR>\n" );
document.write( "With x-axis thru the 2 points, (-90,0) and (90,0), the Origin at (0,0), 3 points are given.<BR>\n" );
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document.write( "y = ax^2 + bx + c<BR>\n" );
document.write( "For the point (0,40):<BR>\n" );
document.write( "40 = a*0 + b*0 + c<BR>\n" );
document.write( "----> c = 40<BR>\n" );
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document.write( "0 = a*8100 + 90b + 40 for the point (90,0)<BR>\n" );
document.write( "0 = a*8100 - 90b + 40 for the point (-90,0)<BR>\n" );
document.write( "--------------------------------------------------- Add<BR>\n" );
document.write( "16200a = -80<BR>\n" );
document.write( "a = -1/202.5<BR>\n" );
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document.write( "0 = a*8100 + 90b + 40 for the point (90,0)<BR>\n" );
document.write( "0 = -40 + 90b + 40<BR>\n" );
document.write( "b = 0<BR>\n" );
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document.write( "---> y = -x^2/202.5 + 40<BR>\n" );
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document.write( "Find y at x = 10<BR>\n" );
document.write( "y = 40 - 100/202.5<BR>\n" );
document.write( "y =~ 39.5 feet above the water.<BR>\n" );
document.write( "---> clearance for 39 feet\r<BR>\n" );
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document.write( " </SPAN>\n" );
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