document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=605201>Question 605201</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a ball is thrown vertically upward from the ground. its distance in feet from the ground in t seconds is s=-16t^2+96t. after how many seconds will the ball be 128 feet from the ground </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #381585 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=381585\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">     a ball is thrown vertically upward from the ground. its distance in feet from the ground in t seconds is s=-16t^2+96t. after how many seconds will the ball be 128 feet from the ground<BR>\n" );
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document.write( "Set s to 128 and solve for t:<BR>\n" );
document.write( "s=-16t^2+96t<BR>\n" );
document.write( "128=-16t^2+96t<BR>\n" );
document.write( "dividing both sides by -16:<BR>\n" );
document.write( "-8 = t^2-6t<BR>\n" );
document.write( "0 = t^2-6t+8<BR>\n" );
document.write( "factoring:<BR>\n" );
document.write( "0 = (t-2)(t-4)<BR>\n" );
document.write( "t = {2,4}<BR>\n" );
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document.write( "answer: <BR>\n" );
document.write( "the ball is 128 feet from the ground at<BR>\n" );
document.write( "2 seconds and again at 4 seconds </SPAN>\n" );
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