document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=118874>Question 118874</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If an object is given an initial velocity of v0 feet per second from a height of S0 feet, then its height S after t seconds is given by the formula S= -16t SQRD+vt+S .  A rock is thrown into the air at 26 feet per second from a height of 13 feet. How long does it take to reach the earth? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #87093 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=87093\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If an object is given an initial velocity of v0 feet per second from a height of S0 feet, then its height S after t seconds is given by the formula S= -16t SQRD+vt+S . A rock is thrown into the air at 26 feet per second from a height of 13 feet. How long does it take to reach the earth?<BR>\n" );
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document.write( "We can write it, the ground would be 0 ft;<BR>\n" );
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document.write( "-16t^2 + 26t + 13 = 0<BR>\n" );
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document.write( "Use the quadratic formula to solve this equation: a=-16; b=26; c=13<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"t+=+%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" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-26+%2B-+sqrt%2826%5E2-4%2A-16%2A13+%29%29%2F%282%2A-16%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-26+%2B-+sqrt%2826%5E2-4%2A-16%2A13+%29%29%2F%282%2A-16%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Do the math here.<BR>\n" );
document.write( "you should get a positive solution of t = 2.026 sec to reach the ground<BR>\n" );
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document.write( "Check your solution in the original equation  <BR>\n" );
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