document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1035819>Question 1035819</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Benjamin threw a rock straight up from a cliff that was 48 ft above the water. If the height of the rock h, in feet, after t seconds is given by the equation h=-16t^2+52t+48, how many seconds will it take for the rock to hit the water?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #650446 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=650446\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The rock hits the water when <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+h+=+0+ ALIGN=MIDDLE  ALT=\"+h+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+h+=+-16t%5E2+%2B+52t+%2B+48+ ALIGN=MIDDLE  ALT=\"+h+=+-16t%5E2+%2B+52t+%2B+48+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0+=+-16t%5E2+%2B+52t+%2B+48+ ALIGN=MIDDLE  ALT=\"+0+=+-16t%5E2+%2B+52t+%2B+48+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Divide both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4+ ALIGN=MIDDLE  ALT=\"+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-4t%5E2+%2B+13t+%2B+12+=+0+ ALIGN=MIDDLE  ALT=\"+-4t%5E2+%2B+13t+%2B+12+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Use quadratic formula<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( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+=+-4+ ALIGN=MIDDLE  ALT=\"+a+=+-4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+=+13+ ALIGN=MIDDLE  ALT=\"+b+=+13+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+c+=+12+ ALIGN=MIDDLE  ALT=\"+c+=+12+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+-13+%2B-+sqrt%28+13%5E2+-+4%2A%28-4%29%2A12+%29%29+%2F+%282%2A%28-4%29%29+ ALIGN=MIDDLE  ALT=\"+t+=+%28+-13+%2B-+sqrt%28+13%5E2+-+4%2A%28-4%29%2A12+%29%29+%2F+%282%2A%28-4%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+-13+%2B-+sqrt%28+169+%2B+192+%29%29+%2F+%28-8%29+ ALIGN=MIDDLE  ALT=\"+t+=+%28+-13+%2B-+sqrt%28+169+%2B+192+%29%29+%2F+%28-8%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+-13+%2B-+sqrt%28+361+%29%29+%2F+%28-8%29+ ALIGN=MIDDLE  ALT=\"+t+=+%28+-13+%2B-+sqrt%28+361+%29%29+%2F+%28-8%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+-13+-+19+%29+%2F+%28-8%29+ ALIGN=MIDDLE  ALT=\"+t+=+%28+-13+-+19+%29+%2F+%28-8%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+-32+%29+%2F+%28-8+%29+ ALIGN=MIDDLE  ALT=\"+t+=+%28+-32+%29+%2F+%28-8+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+4+ ALIGN=MIDDLE  ALT=\"+t+=+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Note that I had to use the negative square root of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+361+ ALIGN=MIDDLE  ALT=\"+361+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "so that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+ ALIGN=MIDDLE  ALT=\"+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > came out to be positive<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "The rock takes 4 sec to hit the water<BR>\n" );
document.write( "--------------------------------<BR>\n" );
document.write( "Here's the plot:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+400%2C+400%2C+-2%2C+6%2C+-10%2C+100%2C+-16x%5E2+%2B+52x+%2B+48+%29+ ALIGN=MIDDLE  ALT=\"+graph%28+400%2C+400%2C+-2%2C+6%2C+-10%2C+100%2C+-16x%5E2+%2B+52x+%2B+48+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );