document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=109868>Question 109868</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780073052816/algebrahomeworkh>Beginning and Intermediate Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> In football, the hangtime of a punt is how many seconds after it's kicked that the ball returns to ground level. The height of one particular punt is given by:<BR>\n" );
document.write( "             <BR>\n" );
document.write( "       y=-16x2 +80x<BR>\n" );
document.write( "where y is in feet, and x is secinds after the puntWhich intercept tells us the hang time of the punt, and what is it?<BR>\n" );
document.write( "  *x-intercept: 0 seconds<BR>\n" );
document.write( "  *x-intercept: 5 seconds<BR>\n" );
document.write( "  *y-intercept: 5 seconds<BR>\n" );
document.write( "  *y-intercept: 3 seconds </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #80148 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=80148\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In football, the hangtime of a punt is how many seconds after it's kicked that the ball returns to ground level. The height of one particular punt is given by:\r<BR>\n" );
document.write( "\n" );
document.write( "y =-16x2 + 80x<BR>\n" );
document.write( "where y is in feet, and x is seconds after the punt Which intercept tells us the hang time of the punt, and what is it?<BR>\n" );
document.write( "*x-intercept: 0 seconds<BR>\n" );
document.write( "*x-intercept: 5 seconds<BR>\n" );
document.write( "*y-intercept: 5 seconds<BR>\n" );
document.write( "*y-intercept: 3 seconds<BR>\n" );
document.write( ":<BR>\n" );
document.write( "When the ball hits the ground y = 0<BR>\n" );
document.write( "-16x^2 + 80x = 0<BR>\n" );
document.write( "Simplify, factor out -16x, (also changes the signs)<BR>\n" );
document.write( "-16x(x - 5) = 0<BR>\n" );
document.write( "x = +5 seconds hang-time (x intercept of course) </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );