document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=452889>Question 452889</A>: <I><SPAN STYLE=\"word-break: break-all;\"> an object that is projected straight downward with an initial velocity of v per second travels a distance s = vt + 9t^2, where t=time in seconds. if dan is standing on a balcony 176 feet above the ground and throws a penny straight downward with an intial velocity of 8 feet per second, in how many seconds will it reach 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 #311527 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=311527\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> an object that is projected straight downward with an initial velocity of v per second travels a distance s = vt + 9t^2, where t=time in seconds. if dan is standing on a balcony 176 feet above the ground and throws a penny straight downward with an intial velocity of 8 feet per second, in how many seconds will it reach the ground?<BR>\n" );
document.write( "..<BR>\n" );
document.write( "When the object reaches the ground it will have traveled 176 feet<BR>\n" );
document.write( "176=8t+9t^2<BR>\n" );
document.write( "9t^2+8t-176=0<BR>\n" );
document.write( "solve by following quadratic formula<BR>\n" );
document.write( "..<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "..<BR>\n" );
document.write( "a=9, b=8, c=-176<BR>\n" );
document.write( "t=[-8ħsqrt(8^2-4*9*-176)]/2*9<BR>\n" );
document.write( "t=[-8ħsqrt(6400)]/18<BR>\n" );
document.write( "t=(-8ħ80)/18<BR>\n" );
document.write( "t=72/18=4 sec<BR>\n" );
document.write( "or<BR>\n" );
document.write( "t=-88/18=-4.88..(reject, time&#8805;0)<BR>\n" );
document.write( "ans:<BR>\n" );
document.write( "The object wll reach the ground in 4 seconds. </SPAN>\n" );
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