document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=176381>Question 176381</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose Charlie O'Brian of the Braves hits a baseball straight upward at 150ft/sec from a height of 5 ft.  \r<BR>\n" );
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document.write( "If an object is given an initial velocity of v feet/second from a height of s feet, then its height S after t seconds is given by the formula <BR>\n" );
document.write( "S= -16t^2 + vt + s. \r<BR>\n" );
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document.write( "a.  Use the formula to determine how long it takes the ball to return to earth.<BR>\n" );
document.write( "b.  Estimate the maximum height reached by the ball. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #131484 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=131484\">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 150ft/sec from a height of 5 ft. <BR>\n" );
document.write( "If an object is given an initial velocity of v feet/second from a height of s feet, then its height S after t seconds is given by the formula <BR>\n" );
document.write( "S(t) = -16t^2 + vt + s. <BR>\n" );
document.write( "a. Use the formula to determine how long it takes the ball to return to earth.<BR>\n" );
document.write( "At earth its height will be zero.<BR>\n" );
document.write( "-16t^2 + 150t + 5 = 0<BR>\n" );
document.write( "t = [-150 +- sqrt(150^2 - 4*-16*5)]/-32<BR>\n" );
document.write( "t = [-150 +- sqrt(22820)]/-32<BR>\n" );
document.write( "Positive solution:<BR>\n" );
document.write( "t = [-150 - 151.063]/-32<BR>\n" );
document.write( "t = 9.408 seconds<BR>\n" );
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document.write( "b. Estimate the maximum height reached by the ball.<BR>\n" );
document.write( "Max occurs when t = -b/2a = -150/[-32] = 4.6875 seconds<BR>\n" );
document.write( "S(4.6875) = -16(4.6875)^2 + 150(4.6875) + 5 = 356.56 ft.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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