document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=77326>Question 77326</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Problem #36(this problem is driving me crazy among two other ones more)\r<BR>\n" );
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document.write( "A ball is thrown upward from the roof of a building 100m tall with an initial velocity of 20m/s. Use this information for exercises 35 to 38.Please show all your steps and the answer in radical form.\r<BR>\n" );
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document.write( "The equation for the hieght of the ball is: h = -5t^2+20t+100\r<BR>\n" );
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document.write( "When will the ball reach a height of 80m? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #55454 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=55454\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> h = -5t^2+20t+100 <BR>\n" );
document.write( "When will the ball reach a height of 80m?<BR>\n" );
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document.write( "80 = -5t^2+20t+100<BR>\n" );
document.write( "-5t^2+20t+20=0<BR>\n" );
document.write( "t^2-4t-4=0<BR>\n" );
document.write( "t=[4+sqrt(16-4*-4]/2<BR>\n" );
document.write( "t=[4+sqrt(32)]/2<BR>\n" );
document.write( "t=[4+4sqrt2]/2<BR>\n" );
document.write( "t=2+2sqrt2 seconds<BR>\n" );
document.write( "=========<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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