document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=338864>Question 338864</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this :<BR>\n" );
document.write( "If an object is thrown vertically upward from the ground with initial speed of 160 feet per second, its height (in feet) t seconds later is given by the function H(t) = -16t^2 + 160t<BR>\n" );
document.write( "a) graph the function H(t)<BR>\n" );
document.write( "b) use the graph in part a) to determine when the object will hit the ground<BR>\n" );
document.write( "c) use the graph in part (a) to estimate how high the object will rise.\r<BR>\n" );
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document.write( "I think b) 4 seconds<BR>\n" );
document.write( "             c) 5 feet\r<BR>\n" );
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document.write( "Thank you for sending me correct answer </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #243153 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=243153\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the graph is a downward opening parabola<BR>\n" );
document.write( "the maximum height is at the vertex , on the axis of symmetry\r<BR>\n" );
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document.write( "the general equation for the axis of symmetry is ___ x = -b / (2a)<BR>\n" );
document.write( "___ in this case ___ x = -160 / [2(-16)] = 5\r<BR>\n" );
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document.write( "H(5) = -16(5^2) + 160(5) = 400\r<BR>\n" );
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document.write( "so the max height is 400 ft and it takes 5 sec to get there\r<BR>\n" );
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document.write( "time up equals time down , so the \"flight\" time is 10 sec </SPAN>\n" );
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