document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=162802>Question 162802</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can anyone help me please, thanks a lot<BR>\n" );
document.write( "Suppose Charlie O’Brian of the braves hits a baseball straight upward at 150 ft/sec from a height of 5 ft. Use the formula to determine how long it takes the ball to return to 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 #120009 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=120009\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Suppose Charlie O’Brian of the braves hits a baseball straight upward at 150 ft/sec from a height of 5 ft. Use the formula to determine how long it takes the ball to return to the earth. <BR>\n" );
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document.write( "Let t = time in seconds<BR>\n" );
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document.write( "The formula has 3 parts, <BR>\n" );
document.write( "gravity, -16t^2; negative because it pulls downward<BR>\n" );
document.write( "upward velocity, 150t positive because it's going upward<BR>\n" );
document.write( "initial height, 5 ft; it starts from 5 ft above the ground<BR>\n" );
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document.write( "The formula<BR>\n" );
document.write( "h = -16t^2 + 150t + 5<BR>\n" );
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document.write( "When it returns to earth h = 0, therefore:<BR>\n" );
document.write( "-16t^2 + 150t + 5 = 0<BR>\n" );
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document.write( "We have to use the quadratic formula to solve for t:<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( "In this problem: a=-16; b=150; c=5<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-150+%2B-+sqrt%28150%5E2+-+4%2A-16%2A5+%29%29%2F%282%2A-16%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-150+%2B-+sqrt%28150%5E2+-+4%2A-16%2A5+%29%29%2F%282%2A-16%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+=+%28-150+%2B-+sqrt%2822500+%2B+320+%29%29%2F%28-32%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-150+%2B-+sqrt%2822500+%2B+320+%29%29%2F%28-32%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+=+%28-150+%2B-+sqrt%2822820%29%29%2F%28-32%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-150+%2B-+sqrt%2822820%29%29%2F%28-32%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "We want the positive solution here:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-150+-+151%29%2F%28-32%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-150+-+151%29%2F%28-32%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-301%29%2F%28-32%29 ALIGN=MIDDLE  ALT=\"%28-301%29%2F%28-32%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = + 9.4 sec to return to earth </SPAN>\n" );
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