document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=987005>Question 987005</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A small rock sits on the edge of a tall building. A strong wind blows the rock off the edge. The distance, in feet, between the rock and the ground tseconds after the rock leaves the edge is given by d=&#8722;16t2&#8722;5t+470.<BR>\n" );
document.write( "If the answer is not an integer, enter it as a decimal. Round to the nearest hundredth<BR>\n" );
document.write( "How many seconds after the rock leaves the edge is it 446feet from the ground?How many seconds after the rock leaves the edge does it hit the ground?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #607853 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=607853\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A small rock sits on the edge of a tall building.<BR>\n" );
document.write( " A strong wind blows the rock off the edge.<BR>\n" );
document.write( " The distance, in feet, between the rock and the ground t seconds after the rock leaves the edge is given by d = &#8722;16t^2 &#8722; 5t + 470.<BR>\n" );
document.write( "If the answer is not an integer, enter it as a decimal. Round to the nearest hundredth<BR>\n" );
document.write( ":<BR>\n" );
document.write( "From the given formula we can surmise that the cliff is 470 above the ground below, which is the reference; d = 0<BR>\n" );
document.write( ":<BR>\n" );
document.write( "How many seconds after the rock leaves the edge is it 446feet from the ground?<BR>\n" );
document.write( "&#8722;16t^2 &#8722; 5t + 470 = 446<BR>\n" );
document.write( "&#8722;16t^2 &#8722; 5t + 470 - 446 = 0<BR>\n" );
document.write( "&#8722;16t^2 &#8722; 5t + 24 = 0<BR>\n" );
document.write( "Using the quadratic formula <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where<BR>\n" );
document.write( "a = -16; b = -5; c = 24<BR>\n" );
document.write( "I got a positive solution of s = 1.08 seconds<BR>\n" );
document.write( ":<BR>\n" );
document.write( "How many seconds after the rock leaves the edge does it hit the ground?<BR>\n" );
document.write( "d = 0<BR>\n" );
document.write( "&#8722;16t^2 &#8722; 5t + 470 = 0<BR>\n" );
document.write( "Now a = -16; b = -5; c = 470<BR>\n" );
document.write( "I got a positive solution of s = 5.27 seconds </SPAN>\n" );
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