document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=143954>Question 143954</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0321227573/algebrahomeworkh>College Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> PROBLEM: HEIGHT OF A PRJECTILE:<BR>\n" );
document.write( "A PROJECTILE IS LAUNCHED FROM GROUND LEVEL WITH AN INITIAL VELOCITY OF v0 FEET PER SECOND. NEGLECTING AIR RESISTANCE, ITS HEIGHT IN FEET t SECONDS AFTER LAUCH IS GIVEN BY s = -16^2+ v0t<BR>\n" );
document.write( "::: IN NUMBER 25, FIND THE TIME (s) THAT THE PROJECTILE WILL (a)REACH A HEIGHT OF 80ft AND (b) RETURN TO THE GROUND FOR THE GIVEN VALUE OF v0. ROUND ANSWERS TO THE NEAREST HUNDREDTH IF NECESSARY.<BR>\n" );
document.write( "** ON THIS PROBLEM I DO NOT KNOW EVEN WHERE TO BEGIN..? ALL OF THE SIGN AND WORDING IS VERY DIFFICULT FOR ME TO COMPREHEND.. PLEASE HELP??.. :) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #104745 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=104745\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> s(t) = -16t^2+ vot<BR>\n" );
document.write( "Comment: s(t) is the height of the projectile after t seconds.<BR>\n" );
document.write( "vo=96 ft/sec is the velocity of the projectile when you let go of it. <BR>\n" );
document.write( "::: IN NUMBER 25, FIND THE TIME (t) THAT THE PROJECTILE WILL <BR>\n" );
document.write( "(a)REACH A HEIGHT OF 80ft :<BR>\n" );
document.write( "80 = -16t^2 + 96t<BR>\n" );
document.write( "-16t^2+96t-80= 0<BR>\n" );
document.write( "-16(t^2-6t+5)=0<BR>\n" );
document.write( "(t-1)(t-5)=0<BR>\n" );
document.write( "t = 1 or t=5<BR>\n" );
document.write( "The projectile reaches a height of 80 ft. after 1 second (on the way up)<BR>\n" );
document.write( "and at 5 seconds (on the way down).<BR>\n" );
document.write( "-------\r<BR>\n" );
document.write( "\n" );
document.write( "(b) RETURN TO THE GROUND FOR THE GIVEN VALUE OF v0=96 ft/sec. <BR>\n" );
document.write( "ROUND ANSWERS TO THE NEAREST HUNDREDTH IF NECESSARY.<BR>\n" );
document.write( "-16t^2+96t=0<BR>\n" );
document.write( "-16t(t-6)=0<BR>\n" );
document.write( "t = 0 or t=6<BR>\n" );
document.write( "It's on the ground at time=0 and again at time = 6 seconds.<BR>\n" );
document.write( "===============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "=================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );