document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1058228>Question 1058228</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a projectile is shot vertically into the air (from the ground) with an initial<BR>\n" );
document.write( "velocity of 176 feet per second, its distance y (in feet) above the ground t<BR>\n" );
document.write( "seconds after it is shot is given by y=176t+16t^2 (neglecting air resistance)<BR>\n" );
document.write( "a. Find the time when y = 0 and interpret the results physically.<BR>\n" );
document.write( "b. Find the times when the projectile is 16 feet off the ground. Compute answer<BR>\n" );
document.write( "to two decimal places. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #673253 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=673253\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y=0.  Note, the square term is always negative.<BR>\n" );
document.write( "-16t^2+176t=0<BR>\n" );
document.write( "-16t(t-11)=0<BR>\n" );
document.write( "t=0, t=11<BR>\n" );
document.write( "t=0 is the starting point; t=11 the end point, when it hits the ground.<BR>\n" );
document.write( "When the projectile is 16 feet off the ground, -16t^2+176t=16<BR>\n" );
document.write( "-16t^2+176t-16=0<BR>\n" );
document.write( "factor out a -16<BR>\n" );
document.write( "-16(t^2-11t+1)=0<BR>\n" );
document.write( "t=(1/2)(11+/- sqrt (121-4); sqrt (117)=10.82<BR>\n" );
document.write( "t=(1/2)(11+/- 10.82)<BR>\n" );
document.write( "t=(1/2)(21.82) or (1/2)(0.18)<BR>\n" );
document.write( "t=0.09 sec and 10.91 sec (note symmetry)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28300%2C300%2C-10%2C12%2C-20%2C500%2C-16x%5E2%2B176x-16%29 ALIGN=MIDDLE  ALT=\"graph%28300%2C300%2C-10%2C12%2C-20%2C500%2C-16x%5E2%2B176x-16%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28300%2C300%2C-2%2C2%2C-20%2C500%2C-16x%5E2%2B176x-16%29 ALIGN=MIDDLE  ALT=\"graph%28300%2C300%2C-2%2C2%2C-20%2C500%2C-16x%5E2%2B176x-16%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );