document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=205111>Question 205111</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am an online college student. The name of my book is Blitzer College Algebra 5th edition. This is a student's solution manual. The author is Prentice Hall/Pearson.\r<BR>\n" );
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document.write( "Please help with this problem. I did get part of the solution, but I am not sure how to get the last two parts. This is the problem and what I have so far.\r<BR>\n" );
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document.write( "The path of a falling object is given by the function s=-16t+vot+so where vo represents the initial velocity in ft/sec and so represents the initial height.The variable t is time in seconds, and s is the height of the object in feet.\r<BR>\n" );
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document.write( "a) If a rock is thrown upward with an initial velocity of 32 feet per second from the top os a 40-foot building, write the height equation using this information.<BR>\n" );
document.write( "answer: s=-16t^2+32t+40\r<BR>\n" );
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document.write( "b) How high is the rock after 0.5 seconds?<BR>\n" );
document.write( "answer: 52 feet    solution: s=-16(0.5)^2+32(0.5)+40<BR>\n" );
document.write( "                             s=-16(0.25)+32(0.5)+40<BR>\n" );
document.write( "                             s=-4+32(0.5)=40<BR>\n" );
document.write( "                             s=-4+16+40<BR>\n" );
document.write( "                             s=12+40<BR>\n" );
document.write( "                             s=52 feet\r<BR>\n" );
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document.write( "These next two questions pertain to the same problem, but I am not sure how to get the equations that need to find my answers.\r<BR>\n" );
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document.write( "c) After how many seconds will the rock reach maximum height? \r<BR>\n" );
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document.write( "d) What is the maximum height?\r<BR>\n" );
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document.write( "Your help will be greatly appreciated. Thank you, Rae </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #154827 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=154827\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The path of a falling object is given by the function s=-16t+vot+so where vo represents the initial velocity in ft/sec and so represents the initial height.The variable t is time in seconds, and s is the height of the object in feet. <BR>\n" );
document.write( "a) If a rock is thrown upward with an initial velocity of 32 feet per second from the top os a 40-foot building, write the height equation using this information.<BR>\n" );
document.write( "answer: s=-16t^2+32t+40 <BR>\n" );
document.write( "b) How high is the rock after 0.5 seconds?<BR>\n" );
document.write( "answer: 52 feet solution: s=-16(0.5)^2+32(0.5)+40<BR>\n" );
document.write( "s=-16(0.25)+32(0.5)+40<BR>\n" );
document.write( "s=-4+32(0.5)=40<BR>\n" );
document.write( "s=-4+16+40<BR>\n" );
document.write( "s=12+40<BR>\n" );
document.write( "s=52 feet <BR>\n" );
document.write( "These next two questions pertain to the same problem, but I am not sure how to get the equations that need to find my answers. <BR>\n" );
document.write( "c) After how many seconds will the rock reach maximum height?<BR>\n" );
document.write( "If you use derivatives, set the 1st derivative to zero.<BR>\n" );
document.write( "h(t) = -16t^2 + 32t + 40<BR>\n" );
document.write( "h' = -32t + 32 = 0<BR>\n" );
document.write( "t = 1 second.<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "Without using derivatives:<BR>\n" );
document.write( "Find the time when the rock is back at 40 feet.<BR>\n" );
document.write( "-16t^2 + 32t + 40 = 40<BR>\n" );
document.write( "t = 2 seconds.<BR>\n" );
document.write( "Since rise time to max and the time back to 40' is equal, the time to max ht. is 1/2 of the 2 seconds.<BR>\n" );
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document.write( "d) What is the maximum height? <BR>\n" );
document.write( "max ht = h(1) = -16 + 32 + 40<BR>\n" );
document.write( "= 56 feet. </SPAN>\n" );
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