document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1110582>Question 1110582</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A bridge spans a river. Its two towers are 3500 feet apart and rise 323 feet above the road. The cable between the towers has the shape of a parabola and the cable just touches the sides of the road midway between the towers. The parabola is positioned in a rectangular coordinate system with its vertex at the origin. The point &#8203;(1750&#8203;,323&#8203;) lies on the&#8203; parabola, as shown. Complete parts a and b.\r<BR>\n" );
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document.write( "a. Write an equation in the form y=ax`2 the parabolic cable. Do this by substituting 1750 for x and 323 for y and determining the value of a.\r<BR>\n" );
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document.write( "y=_____x`2 &#8203;(Round to seven decimal places as&#8203; needed.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #725699 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=725699\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A bridge spans a river. Its two towers are 3500 feet apart and rise 323 feet above the road. The cable between the towers has the shape of a parabola and the cable just touches the sides of the road midway between the towers. The parabola is positioned in a rectangular coordinate system with its vertex at the origin. The point (1750,323) lies on the parabola, as shown. Complete parts a and b.\r<BR>\n" );
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document.write( "a. Write an equation in the form y=ax`2 the parabolic cable. Do this by substituting 1750 for x and 323 for y and determining the value of a.<BR>\n" );
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document.write( "Three points are known: (-1750,323), (0,0) and (1750,323)<BR>\n" );
document.write( "ax^2 + bx + c = 0 is the parabola.<BR>\n" );
document.write( "c = 0 since the vertex is at the Origin.<BR>\n" );
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document.write( "y = ax^2 + bx<BR>\n" );
document.write( "ax^2 + bx = y<BR>\n" );
document.write( "a*(-1750)^2 - 1750b = 323<BR>\n" );
document.write( "a*1750^2 + 1750b = 323<BR>\n" );
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document.write( "2a*1750^2 = 646<BR>\n" );
document.write( "a =~ 0.00010546939<BR>\n" );
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document.write( "b = 0<BR>\n" );
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document.write( "y = 0.00010546939x^2\r<BR>\n" );
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document.write( " </SPAN>\n" );
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