document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=523948>Question 523948</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I do not understand the process to solve this problem:\r<BR>\n" );
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document.write( "A model rocket is launched with an initial upward velocity of 50 m/s . The rocket's height h (in meters) after t seconds is given by the following.<BR>\n" );
document.write( "h=50t-5t^2\r<BR>\n" );
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document.write( "Find all values of  for which the rocket's height is  30 meters. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #347480 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=347480\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A model rocket is launched with an initial upward velocity of 50 m/s . The rocket's height h (in meters) after t seconds is given by the following.<BR>\n" );
document.write( "h=50t-5t^2\r<BR>\n" );
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document.write( "Find all values of  for which the rocket's height is  30 meters.<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+50t+-+5t%5E2+=+30 ALIGN=MIDDLE  ALT=\"h+=+50t+-+5t%5E2+=+30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10t+-+t%5E2+=+6 ALIGN=MIDDLE  ALT=\"10t+-+t%5E2+=+6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5E2+-+10t+%2B+6+=+0 ALIGN=MIDDLE  ALT=\"t%5E2+-+10t+%2B+6+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "t = (10/2) - sqrt(100 - 24)/2 seconds going up<BR>\n" );
document.write( "t = 5 - sqrt(19) =~ 0.6411 seconds ascending<BR>\n" );
document.write( "t = 5 + sqrt(19) =~ 9.359 seconds coming back down.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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