document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=490126>Question 490126</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am having trouble solving the following:  Please help me understand\r<BR>\n" );
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document.write( "Height , h metres of a model rocket above ground, t = seconds after launching is given by the equation h=4t(50-t).\r<BR>\n" );
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document.write( "Sketch the graph show the co-ordinates of all intercepts and turning point.\r<BR>\n" );
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document.write( "I need to find the greatest height the rocket reaches, after how long does the rocket reach its greatest height and how long does the rockets flight last.\r<BR>\n" );
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document.write( "I have not come across a quadratic equation in this form before and it is confusing me.\r<BR>\n" );
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document.write( "Any help you can give me would be most appreciated.\r<BR>\n" );
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document.write( "Thank you.<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 #333868 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=333868\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Height , h metres of a model rocket above ground, t = seconds after launching is given by the equation h(t) = 4t(50-t). <BR>\n" );
document.write( "Sketch the graph show the co-ordinates of all intercepts and turning point.<BR>\n" );
document.write( "h(t) = -4t^2+200t<BR>\n" );
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document.write( "Vertical intercept: (0,0)<BR>\n" );
document.write( "Horizontal intercept: (0,0)(50,0)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28400%2C400%2C-10%2C60%2C-10%2C2600%2C-4x%5E2%2B200x%29 ALIGN=MIDDLE  ALT=\"graph%28400%2C400%2C-10%2C60%2C-10%2C2600%2C-4x%5E2%2B200x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "I need to find the greatest height the rocket reaches, after how long does the rocket reach its greatest height and how long does the rockets flight last.<BR>\n" );
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document.write( "Max occurs when t = -b/(2a) = -200/(2*-4) = 25 seconds<BR>\n" );
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document.write( "Max height: h(25) = 4*25(25) = 2500 ft<BR>\n" );
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document.write( "length of flight: 50 seconds<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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