document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1013573>Question 1013573</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The height h (in feet) above the ground of a baseball depends upon the time t (in seconds) it has been in flight. Cameron takes a mighty swing, but hits a bloop sinlge whose height is described approximately by the equation h=-5t^2+45t+17. Ho long is the ball in the air? The ball reaches its maximum heght after how many seconds of light? What is the maximum height?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #630001 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=630001\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The height h (in feet) above the ground of a baseball depends upon the time t (in seconds) it has been in flight. Cameron takes a mighty swing, but hits a bloop sinlge whose height is described approximately by the equation h=-5t^2+45t+17. How long is the ball in the air? The ball reaches its maximum heght after how many seconds of light? What is the maximum height?\r<BR>\n" );
document.write( "\n" );
document.write( "h=-5t^2+45t+17<BR>\n" );
document.write( "complete the square<BR>\n" );
document.write( "h=-5(t^2+9t+20.25)+101.25+17<BR>\n" );
document.write( "h=-5(t+4.5)^2+118.25<BR>\n" );
document.write( "This is an equation of a parabola that opens downward wwith vertex at (4.5,118.25)<BR>\n" );
document.write( "maximum height of118.25 ft is reached after 4.5 seconds of flight.\r<BR>\n" );
document.write( "\n" );
document.write( "Set h=0<BR>\n" );
document.write( "=-5t^2+45t+17=0\r<BR>\n" );
document.write( "\n" );
document.write( "solve for t by quadratic equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "a=-5, b=45, c=17<BR>\n" );
document.write( "ans: t=9.36<BR>\n" );
document.write( " How long is the ball in the air? 9.36 seconds </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );