document.write( "Question 140798: The path of a fallen object is given by the function s= -16t^2+v0t+s0, where v0 represents the initial velocity in ft/sec and s0 represents the initial height. The variable t is time in seconds and s is the height of the object in feet.\r
\n" ); document.write( "\n" ); document.write( "If a rock is thrown upward with an initial velocity of 32 feet per second from the top of a 40 foot building,how high is the rock after 0.5 seconds? After how many seconds will the rock reach maximum height?\r
\n" ); document.write( "\n" ); document.write( "Ive already answered the first question, i think it is 52 feet. Is this correct?
\n" ); document.write( "How do i set up my equation to answer the second question? (step by step please)
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Algebra.Com's Answer #102507 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
PART ONE
\n" ); document.write( "\"s=+-16t%5E2%2Bv%5B0%5Dt%2Bs%5B0%5D\"
\n" ); document.write( "\"s%280.5%29=+-16%280.5%29%5E2%2B32%280.5%29%2B40\"
\n" ); document.write( "\"s%280.5%29=+-16%280.25%29%2B16%2B40\"
\n" ); document.write( "\"s%280.5%29=+-4%2B16%2B40\"
\n" ); document.write( "\"s%280.5%29=+52\"
\n" ); document.write( "Yes, you are correct.
\n" ); document.write( "52 feet is the correct height.
\n" ); document.write( "PART TWO\r
\n" ); document.write( "\n" ); document.write( "I'm not sure how advanced you are in mathematics to solve the next part.
\n" ); document.write( "If you have taken calculus, you take the derivative of the function and set it equal to zero.
\n" ); document.write( "If you are using algebra, you can recognize that the equation is the equation of a parabola, find the axis of symmetry, and calculate the maximum there.
\n" ); document.write( "Finally you could plot points and try to find the maximum that way.
\n" ); document.write( "We can do all three.
\n" ); document.write( "1.\"s=+-16t%5E2%2B32t%2B40\"
\n" ); document.write( "\"ds%2Fdt=-32t%2B32=0\"
\n" ); document.write( "\"-32t%2B32=0\"
\n" ); document.write( "\"t=1\"
\n" ); document.write( "The maximum occurs at t=1 second.
\n" ); document.write( "\"s%281%29=-16%281%29%2B32%281%29%2B40\"
\n" ); document.write( "\"s%281%29=56\"
\n" ); document.write( "2.\"s=+-16t%5E2%2B32t%2B40\"
\n" ); document.write( "The axis of symmetry for the parabola
\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\" occurs at \"x=-b%2F2a\"
\n" ); document.write( "In your case,
\n" ); document.write( "a=-16
\n" ); document.write( "b=32
\n" ); document.write( "The axis of symmetry is then
\n" ); document.write( "\"t=-32%2F2%28-16%29\"
\n" ); document.write( "\"t=1\"
\n" ); document.write( "Just as above, s=56 ft at t=1 sec.
\n" ); document.write( "3. Start at t=0 and solve for s.
\n" ); document.write( "(0.0,40)
\n" ); document.write( "(0.5,52)
\n" ); document.write( "(1.0,56)
\n" ); document.write( "(1.5,52)
\n" ); document.write( "(2.0,40)
\n" ); document.write( "You could also take some points aroung t=1 to prove to yourself that the maximum does occur at t=1.
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