document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=118531>Question 118531</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A flare is fired as a stress signal and its height ,h in metres above the ground, t seconds after firing, is provided in the table below. Algebraically determine the quadratic function that defines the height of the flare above the ground t seconds after firing, and use it to determine the flare's height at 2.4 seconds.\r<BR>\n" );
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document.write( "t---0 1   2   3   4  <BR>\n" );
document.write( "h---2 97 182 257 322<BR>\n" );
document.write( "I tried y=-2ak^2<BR>\n" );
document.write( "97=-2a(1)^2<BR>\n" );
document.write( "97/-2=-2a/-2<BR>\n" );
document.write( "a=-48.5  and was completly lost :( Please Help Me :) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #86641 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=86641\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the general equation is h=at^2+bt+c\r<BR>\n" );
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document.write( "by plugging in values from the table, you can find the values for a, b, and c\r<BR>\n" );
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document.write( "when t=0, h=c ___ so c=2\r<BR>\n" );
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document.write( "when t=1, 97=a+b+2 ___ 95=a+b ___ 95-a=b\r<BR>\n" );
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document.write( "when t=2, 182=4a+2b+2 ___ 180=4a+2b ___ 90=2a+b\r<BR>\n" );
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document.write( "substitution gives 90=2a+(95-a) ___ -5=a ___ 95-(-5)=b ___ 100=b\r<BR>\n" );
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document.write( "h=-5t^2+100t+2\r<BR>\n" );
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document.write( "in the real world, the a term is half the gravitational acceleration (negative because gravity is downward)<BR>\n" );
document.write( "___ the b term is the initial velocity of the flare<BR>\n" );
document.write( "___ and the c term is the initial height (probably the height of the person shooting the flare) </SPAN>\n" );
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