document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=553584>Question 553584</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello! I have a word problem and I have no idea how to solve it, if you could solve it and show me the steps:<BR>\n" );
document.write( "A rock is thrown from a top of the tall building. The distance,in feet, between the rock and the ground t seconds after it is thrown is given by d= -16t^2-4t+412. How long after the rock is thrown is it 400 feet from the ground? (answer should be in decimal form) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #360958 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=360958\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Start with:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+-16t%5E2-4t%2B412 ALIGN=MIDDLE  ALT=\"d+=+-16t%5E2-4t%2B412\"   DISABLED_style= \"max-width:90%; height:auto;\" > You are being asked to solve this equation for t when d (distance from the ground) is 400, so you substitute d = 400.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=400+=+-16t%5E2-4t%2B412 ALIGN=MIDDLE  ALT=\"400+=+-16t%5E2-4t%2B412\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 400 from both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+-16t%5E2-4t%2B12 ALIGN=MIDDLE  ALT=\"0+=+-16t%5E2-4t%2B12\"   DISABLED_style= \"max-width:90%; height:auto;\" > Factor -4 to make it a little easier to solve.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-4%284t%5E2%2Bt-3%29+=+0 ALIGN=MIDDLE  ALT=\"-4%284t%5E2%2Bt-3%29+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Factor the trinomial.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4t%5E2%2Bt-3+=+%284t-3%29%28t%2B1%29 ALIGN=MIDDLE  ALT=\"4t%5E2%2Bt-3+=+%284t-3%29%28t%2B1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > so now you have:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-4%284t-3%29%28t%2B1%29+=+0 ALIGN=MIDDLE  ALT=\"-4%284t-3%29%28t%2B1%29+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Apply the zero product rule.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-4+=+0 ALIGN=MIDDLE  ALT=\"-4+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4t-3+=+0 ALIGN=MIDDLE  ALT=\"4t-3+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2B1+=+0 ALIGN=MIDDLE  ALT=\"t%2B1+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-4+=+0 ALIGN=MIDDLE  ALT=\"-4+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > No way!<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4t-3+=+0 ALIGN=MIDDLE  ALT=\"4t-3+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4t+=+3 ALIGN=MIDDLE  ALT=\"4t+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+3%2F4 ALIGN=MIDDLE  ALT=\"t+=+3%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28t+=+0.75%29 ALIGN=MIDDLE  ALT=\"highlight%28t+=+0.75%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2B1+=+0 ALIGN=MIDDLE  ALT=\"t%2B1+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+-1 ALIGN=MIDDLE  ALT=\"t+=+-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > Discard this solution as the time must be a positive quantity.<BR>\n" );
document.write( "The rock will be 400 feet from the ground in 0.75 seconds.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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