document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=821566>Question 821566</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rocket fired vertically upwards follows the law y=48t-8t^2\r<BR>\n" );
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document.write( "Plot a graph y against t for values of t from 0 to 6 seconds\r<BR>\n" );
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document.write( "By solving the quadratic equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+8t2-48t%2Ba=0 ALIGN=MIDDLE  ALT=\"+8t2-48t%2Ba=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > find the times t1 and t2 when the rocker is at a height of 'a' metres above the launch point. \r<BR>\n" );
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document.write( "Value of a is 25 \r<BR>\n" );
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document.write( "Give final answer correct to 3 decimal places and check the answers using your graph.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #494230 by </B><A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><B>TimothyLamb(4379)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><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=TimothyLamb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=494230\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ---<BR>\n" );
document.write( "the equation of projectile motion is given as:<BR>\n" );
document.write( "h(t) = -8t^2 + 48t<BR>\n" );
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document.write( "at a= 25 meters:<BR>\n" );
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document.write( "h(t) = -8t^2 + 48t = 25<BR>\n" );
document.write( "-8t^2 + 48t - 25 = 0<BR>\n" );
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document.write( "the above quadratic equation is in standard form, with a=-8, b=48, and c=-25<BR>\n" );
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document.write( "to solve the quadratic equation, by using the quadratic formula, copy and paste this:<BR>\n" );
document.write( "-8 48 -25<BR>\n" );
document.write( "into this solver: https://sooeet.com/math/quadratic-equation-solver.php<BR>\n" );
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document.write( "the two real roots (i.e. the two x-intercepts), of the quadratic are:<BR>\n" );
document.write( "t = 0.576160071<BR>\n" );
document.write( "t = 5.42383993<BR>\n" );
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document.write( "answer:<BR>\n" );
document.write( "the rocket is at 25 meters height twice, at the following times in seconds after launch:<BR>\n" );
document.write( "t = 0.576160071<BR>\n" );
document.write( "t = 5.42383993<BR>\n" );
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document.write( "graph:<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-2%2C+7%2C+-10%2C+80%2C+-8x%5E2+%2B+48x%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-2%2C+7%2C+-10%2C+80%2C+-8x%5E2+%2B+48x%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Solve and graph linear equations:<BR>\n" );
document.write( "https://sooeet.com/math/linear-equation-solver.php<BR>\n" );
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document.write( "Solve quadratic equations, quadratic formula:<BR>\n" );
document.write( "https://sooeet.com/math/quadratic-formula-solver.php<BR>\n" );
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document.write( "Solve systems of linear equations up to 6-equations 6-variables:<BR>\n" );
document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php </SPAN>\n" );
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