document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1155173>Question 1155173</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rocket is launched from atop a 73-foot cliff with an initial velocity of 142 ft/s. The height of the rocket above the ground at time t is given by h=-16t^2+142t+73.\r<BR>\n" );
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document.write( "A) When will the rocket hit the ground after it is launched? Round to the nearest tenth of a second.(Solve Algebraically, Hint: Use the Quadratic Formula to solve and the round the square root answer one decimal place)\r<BR>\n" );
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document.write( "B) When will the rocket reach 199ft from the ground? (Solve Algebraically) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #777735 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=777735\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  A rocket is launched from atop a 73-foot cliff with an initial velocity of 142 ft/s.<BR>\n" );
document.write( " The height of the rocket above the ground at time t is given by h=-16t^2+142t+73.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "A) When will the rocket hit the ground after it is launched? Round to the nearest tenth of a second.(Solve Algebraically, Hint: Use the Quadratic Formula to solve and the round the square root answer one decimal place)<BR>\n" );
document.write( "h = 0 when it hits the ground<BR>\n" );
document.write( "-16t^2 + 142t + 73 = 0<BR>\n" );
document.write( "The quadratic formula: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"x+=+%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( "a=-16, b=142, c=73<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-142+%2B-+sqrt%28142%5E2-4%2A-16%2A73+%29%29%2F%282%2A-16%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-142+%2B-+sqrt%28142%5E2-4%2A-16%2A73+%29%29%2F%282%2A-16%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-142+%2B-+sqrt%2820164%2B4672+%29%29%2F%28-32%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-142+%2B-+sqrt%2820164%2B4672+%29%29%2F%28-32%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-142+-+sqrt%2824836%29%29%2F-32+%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-142+-+sqrt%2824836%29%29%2F-32+%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >, the positive solution<BR>\n" );
document.write( "do the math<BR>\n" );
document.write( "t = 9.3623 ~ 9.4 seconds<BR>\n" );
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document.write( "B) When will the rocket reach 199ft from the ground? (Solve Algebraically)<BR>\n" );
document.write( "-16t^2 + 142t + 73 = 199<BR>\n" );
document.write( "-16t^2 + 142t + 73 - 199 = 0<BR>\n" );
document.write( "-16t^2 + 142t - 126 = 0<BR>\n" );
document.write( "a=-16; b=-142, c=-126<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-142+%2B-+sqrt%28142%5E2-4%2A-16%2A-126+%29%29%2F%282%2A-16%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-142+%2B-+sqrt%28142%5E2-4%2A-16%2A-126+%29%29%2F%282%2A-16%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-142+%2B-+sqrt%2820164-8064+%29%29%2F%28-32%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-142+%2B-+sqrt%2820164-8064+%29%29%2F%28-32%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-142+-+sqrt%2812100%29%29%2F%28-32%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-142+-+sqrt%2812100%29%29%2F%28-32%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "do the math<BR>\n" );
document.write( "t = 7.875 ~ 7.9 seconds reaches 199 ft the 2nd time<BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-142+%2B+sqrt%2812100%29%29%2F%28-32%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-142+%2B+sqrt%2812100%29%29%2F%28-32%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = 1 second reaches 199 ft the first time\r<BR>\n" );
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document.write( " </SPAN>\n" );
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