document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1131808>Question 1131808</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The height in feet of a projectile with an initial velocity of 96 feet per second and an initial height of 256 feet is a function of time in seconds given by<BR>\n" );
document.write( "h(t) = &#8722;16t2 + 96t + 256.<BR>\n" );
document.write( "(a) Find the maximum height of the projectile._______ft<BR>\n" );
document.write( "(b) Find the time t when the projectile achieves its maximum height.<BR>\n" );
document.write( "t =_____________sec<BR>\n" );
document.write( "(c) Find the time t when the projectile has a height of 0 feet.<BR>\n" );
document.write( "t =___________sec </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #748480 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=748480\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> maximum height is vertex and occurs at t=-b/2a, the formula for the vertex of a quadratic.<BR>\n" );
document.write( "This is -96/-32 or 3 seconds ANSWER for b.<BR>\n" );
document.write( "h(3)=-144+288+256=400 feet ANSWER\r<BR>\n" );
document.write( "\n" );
document.write( "c. changing all signs, 16t^2-96t-256=0<BR>\n" );
document.write( "divide by 16, t^2-6t-16=0<BR>\n" );
document.write( "(t-8)(t+2)=0<BR>\n" );
document.write( "t=8 seconds, only positive root ANSWER.\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28300%2C300%2C-10%2C10%2C-100%2C500%2C-16x%5E2%2B96x%2B256%29 ALIGN=MIDDLE  ALT=\"graph%28300%2C300%2C-10%2C10%2C-100%2C500%2C-16x%5E2%2B96x%2B256%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );