document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=285567>Question 285567</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The height  h (in feet) of a rocket as a function of the time t (in seconds) of flight is given by the following equation. Determine the times t when the rocket is on the ground.\r<BR>\n" );
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document.write( "	h=50+280t-16t(squared)		<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 #206982 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=206982\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+0 ALIGN=MIDDLE  ALT=\"t+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >, the rocket is still on the ground, and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+50 ALIGN=MIDDLE  ALT=\"h+=+50\"   DISABLED_style= \"max-width:90%; height:auto;\" > (height of rocket?)<BR>\n" );
document.write( "The rocket is also on the ground when it comes <BR>\n" );
document.write( "back down at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+0 ALIGN=MIDDLE  ALT=\"h+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16t%5E2+%2B+280t+%2B+50+=+0 ALIGN=MIDDLE  ALT=\"-16t%5E2+%2B+280t+%2B+50+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Using quadratic equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%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+=+-16 ALIGN=MIDDLE  ALT=\"a+=+-16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b+=+280 ALIGN=MIDDLE  ALT=\"b+=+280\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c+=+50 ALIGN=MIDDLE  ALT=\"c+=+50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-280+%2B-+sqrt%28+280%5E2-4%2A%28-16%29%2A50+%29%29%2F%282%2A%28-16%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-280+%2B-+sqrt%28+280%5E2-4%2A%28-16%29%2A50+%29%29%2F%282%2A%28-16%29%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+=+%28-280+%2B-+sqrt%28+78400+%2B+64%2A50+%29%29%2F%28-32%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-280+%2B-+sqrt%28+78400+%2B+64%2A50+%29%29%2F%28-32%29%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+=+%28-280+%2B-+sqrt%28+78400+%2B+3200+%29%29%2F%28-32%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-280+%2B-+sqrt%28+78400+%2B+3200+%29%29%2F%28-32%29%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+=+%28-280+%2B-+sqrt%28+81600+%29%29%2F%28-32%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-280+%2B-+sqrt%28+81600+%29%29%2F%28-32%29%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+=+%28-280+%2B-+285.657%29%2F%28-32%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-280+%2B-+285.657%29%2F%28-32%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The (+) square root gives me negative <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t ALIGN=MIDDLE  ALT=\"t\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( " so I can't use it<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-565.657%29%2F%28-32%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-565.657%29%2F%28-32%29%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+=+17.677 ALIGN=MIDDLE  ALT=\"t+=+17.677\"   DISABLED_style= \"max-width:90%; height:auto;\" > sec<BR>\n" );
document.write( "The rocket comes back to the ground in 17.677sec<BR>\n" );
document.write( "Here's a plot of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h ALIGN=MIDDLE  ALT=\"h\"   DISABLED_style= \"max-width:90%; height:auto;\" > vs <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t ALIGN=MIDDLE  ALT=\"t\"   DISABLED_style= \"max-width:90%; height:auto;\" > also:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+500%2C+500%2C+-5%2C+22%2C+-50%2C+1300%2C+-16x%5E2+%2B+280x+%2B+50%29+ ALIGN=MIDDLE  ALT=\"+graph%28+500%2C+500%2C+-5%2C+22%2C+-50%2C+1300%2C+-16x%5E2+%2B+280x+%2B+50%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );