document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1155249>Question 1155249</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A bridge is built in the shape of a parabolic arch. The bridge arch has a span of 152 feet and a maximum height of 35 feet. Find the height of the arch at 25 feet from its center. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #777805 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=777805\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Let the origin be center of the base of the arch.  The vertex of the parabola is then at (0,35); and two points on the parabola are (-76,0) and (76,0).<br><BR>\n" );
document.write( "The equation of the parabola is of the form<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+35-ax%5E2 ALIGN=MIDDLE  ALT=\"y+=+35-ax%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "where the value of the coefficient a is determined by the point (76,0) on the parabola.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+35-a%2876%5E2%29 ALIGN=MIDDLE  ALT=\"0+=+35-a%2876%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2876%5E2%29+=+35 ALIGN=MIDDLE  ALT=\"a%2876%5E2%29+=+35\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+35%2F76%5E2 ALIGN=MIDDLE  ALT=\"x+=+35%2F76%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "So the equation of the parabola is<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+35-%2835%2F76%5E2%29x%5E2 ALIGN=MIDDLE  ALT=\"y+=+35-%2835%2F76%5E2%29x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28800%2C200%2C-80%2C80%2C-10%2C40%2C35-%2835%2F76%5E2%29x%5E2%29 ALIGN=MIDDLE  ALT=\"graph%28800%2C200%2C-80%2C80%2C-10%2C40%2C35-%2835%2F76%5E2%29x%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "To find the height of the arch 25 feet from its center, simply find the value of y when x is 25.<br><BR>\n" );
document.write( "I leave that much of the problem for you....<br><BR>\n" );
document.write( " </SPAN>\n" );
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