document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=775074>Question 775074</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A man is standing over a beach and throws a rock up in the air from a height of 192ft. the initial velocity is 64 ft. per second.  The rock height=h above the beach, in feet, after t seconds is given by the function\r<BR>\n" );
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document.write( " h(t)= -16t+64t+192<BR>\n" );
document.write( "the -16t has an exponant of 2 but i could not figure out how to do it with my computer.  <BR>\n" );
document.write( "a) how high above the ground is the rock after 2 seconds?<BR>\n" );
document.write( "b) How long will it take for the rock to raech the ground. o ft.?<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 #472638 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=472638\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A man is standing over a beach and throws a rock up in the air from a height of 192ft.<BR>\n" );
document.write( " the initial velocity is 64 ft. per second.<BR>\n" );
document.write( " The rock height=h above the beach, in feet, after t seconds is given by the function<BR>\n" );
document.write( "h(t)= -16t^2 + 64t + 192; Use the \"^\", upper case 6<BR>\n" );
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document.write( "a) how high above the ground is the rock after 2 seconds?<BR>\n" );
document.write( "Replace t with 2, solve for h(2)<BR>\n" );
document.write( "h(2) = -16(2^2) + 64(2) + 192<BR>\n" );
document.write( "h(2) = -64 + 128 + 192<BR>\n" );
document.write( "h(2) = 256ft<BR>\n" );
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document.write( "b) How long will it take for the rock to raech the ground. o ft.?<BR>\n" );
document.write( "The h= 0, so we have<BR>\n" );
document.write( "-16t^2 + 64t + 192 = 0<BR>\n" );
document.write( "Simplify, divide by -16<BR>\n" );
document.write( "t^2 - 4t - 12 = 0<BR>\n" );
document.write( "factors to<BR>\n" );
document.write( "(t-6))(t+2) = 0<BR>\n" );
document.write( "the positive solution is all we want here<BR>\n" );
document.write( "t = 6 sec to reach ground<BR>\n" );
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document.write( "YOu can confirm this by finding h(t) when  t = 6<BR>\n" );
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