document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=609152>Question 609152</A>: <I><SPAN STYLE=\"word-break: break-all;\"> lauren dove into a swimming pool from a 15-foot-high diving board with an intitial upward velocity of 8 feet per second.the equation h(s)= -16s(square root)+8s+15 models the height (H) after (S) after she jumps off the diving board.<BR>\n" );
document.write( "i wanna know how to find the time in seconds,it took lauren to enter the water.<BR>\n" );
document.write( "also i wanna know what was the greatest height lauren reached when diving?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #383637 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=383637\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Lauren dove into a swimming pool from a 15-foot-high diving board with an initial upward velocity of 8 feet per second.<BR>\n" );
document.write( "the equation h(s)= -16s^2 + 8s + 15 models the height (H) after (S) after she jumps off the diving board.<BR>\n" );
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document.write( "Everything we need to know is in the equation<BR>\n" );
document.write( "-16s^2 = the downward velocity of gravity<BR>\n" );
document.write( "+8s = the upward velocity of the diver<BR>\n" );
document.write( "15 = height of the diving board<BR>\n" );
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document.write( "The water; h = 0, so we have<BR>\n" );
document.write( "-16s^2 + 8s + 15 = 0<BR>\n" );
document.write( "you can solve this using the quadratic formula, but this will factor<BR>\n" );
document.write( "Multiply by -1<BR>\n" );
document.write( "16s^2 - 8s - 15 = 0<BR>\n" );
document.write( "(4s - 5)(4s + 3) = 0<BR>\n" );
document.write( "positive solution<BR>\n" );
document.write( "4s = 5<BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F4 ALIGN=MIDDLE  ALT=\"5%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 1.25 seconds to hit the water<BR>\n" );
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document.write( "You can confirm this:<BR>\n" );
document.write( "h = -16(1.25^2) + 8(1.25) + 15<BR>\n" );
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document.write( "\"what was the greatest height Lauren reached when diving?\"<BR>\n" );
document.write( "use the axis of symmetry formula to find s where the max occurs; <BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-8%29%2F%282%2A-16%29 ALIGN=MIDDLE  ALT=\"%28-8%29%2F%282%2A-16%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-8%29%2F%28-32%29 ALIGN=MIDDLE  ALT=\"%28-8%29%2F%28-32%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = .25 seconds<BR>\n" );
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document.write( "Replace s with .25 in the original equation, to find max h<BR>\n" );
document.write( "h = -16(.25^2) + 8(.25) + 15\r<BR>\n" );
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