document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1199568>Question 1199568</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bob threw a ball upward at a velocity of 10 m/s while standing on the roof of a building that was 12 m high.  What was the height of the ball after 2 seconds?\r<BR>\n" );
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document.write( "I am using h= -16t^2 +10t + 12\r<BR>\n" );
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document.write( "if I substitute 2 for t, I get -32.  How can I get negative time? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #833504 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=833504\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First of all, you are solving for the height of the ball, not the time.<BR>\n" );
document.write( "Secondly, you are mixing English units and metric units. We are given the speed<BR>\n" );
document.write( "and height in m/s and m, but in the formula h(t) = h0 + v0*t - 1/2g*t^2, you are<BR>\n" );
document.write( "using g = 32 ft/s^2 instead of g = 9.8 m/s^2. Make the substitution and you will<BR>\n" );
document.write( "get a sensible answer for the height. </SPAN>\n" );
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