document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=724396>Question 724396</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A ball is thrown upward with an initial velocity of 343 m/sec.  When will it be 4900 meters high?  I have been trying to help my son with his Algebra.  I am having such a hard time.  Could some one please show and explain to me an eqation to figure this problem out? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #443726 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=443726\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A ball is thrown upward with an initial velocity of 343 m/sec.  When will it be 4900 meters high?<BR>\n" );
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document.write( "The equation for ht vs. time should be given with the problem.<BR>\n" );
document.write( "If not, the commonly used is<BR>\n" );
document.write( "h(t) = -4.9t^2 + vt + C, t in seconds, h & C in meters<BR>\n" );
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document.write( "h(t) = -4.9t^2 + 343t = 4900<BR>\n" );
document.write( "4.9t^2 - 343t + 4900 = 0<BR>\n" );
document.write( "t^2 - 70t + 1000 = 0<BR>\n" );
document.write( "(t - 20)*(t - 50) = 0<BR>\n" );
document.write( "t = 20 seconds going up<BR>\n" );
document.write( "t = 50 seconds falling<BR>\n" );
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document.write( "That's a good throw, ~ 767 mi/hr<BR>\n" );
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