document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=169835>Question 169835</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me with this problem:\r<BR>\n" );
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document.write( "An object launched upward with an initial velocity of 14.7 m/s from a height of 49 m will have a height of s(t)= -4.9t^2+49, where s is in meters and t is in seconds.  How long will it take the object to hit the ground?\r<BR>\n" );
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document.write( "Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #125240 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=125240\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An object launched upward with an initial velocity of 14.7 m/s from a height of 49 m will have a height of s(t)= -4.9t^2+49, where s is in meters and t is in seconds. How long will it take the object to hit the ground? <BR>\n" );
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document.write( "s(t) must be zero when the object hits the ground.<BR>\n" );
document.write( "-4.9t^2+49 = 0<BR>\n" );
document.write( "4.9t^2 = 49<BR>\n" );
document.write( "t^2 = 49/4.9<BR>\n" );
document.write( "Positive answer: <BR>\n" );
document.write( "t = sqrt(49/4.9)<BR>\n" );
document.write( "t = 3.1622... seconds<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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