document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=386099>Question 386099</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Height of a projectile. The height H, in feet, of a projectile with an initial velocity of 96 ft/sec is given by the equation<BR>\n" );
document.write( "H=-16t squared + 96t<BR>\n" );
document.write( "where t= time, in seconds. Use any equation-solving technique to answer the following questions.<BR>\n" );
document.write( "a) How many seconds after launch is the projectile 128 ft above ground?<BR>\n" );
document.write( "b) When does the projectile reach its maximum height?<BR>\n" );
document.write( "c) How many seconds after launch does the projectile return to the ground?<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #272999 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=272999\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Height of a projectile. The height H, in feet, of a projectile with an initial velocity of 96 ft/sec is given by the equation<BR>\n" );
document.write( "H=-16t squared + 96t<BR>\n" );
document.write( "where t= time, in seconds. Use any equation-solving technique to answer the following questions.<BR>\n" );
document.write( "a) How many seconds after launch is the projectile 128 ft above ground?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=128+=+-16t%5E2+%2B+96t ALIGN=MIDDLE  ALT=\"128+=+-16t%5E2+%2B+96t\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16t%5E2+-+96t+%2B+128+=+0 ALIGN=MIDDLE  ALT=\"16t%5E2+-+96t+%2B+128+=+0\"   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+-+6t+%2B+8+=+0 ALIGN=MIDDLE  ALT=\"t%5E2+-+6t+%2B+8+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(t-4)*(t-2) = 0<BR>\n" );
document.write( "t = 2 seconds (going up)<BR>\n" );
document.write( "t = 4 seconds (descending)<BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "b) When does the projectile reach its maximum height?<BR>\n" );
document.write( "Using the info above, it's at t = 3 seconds.<BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "c) How many seconds after launch does the projectile return to the ground?<BR>\n" );
document.write( "When H = 0<BR>\n" );
document.write( "H=-16t squared + 96t = 0<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5E2+-+6t+=+0 ALIGN=MIDDLE  ALT=\"t%5E2+-+6t+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = 0 (launch)<BR>\n" );
document.write( "t = 6 (impact)<BR>\n" );
document.write( "t in seconds\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );