document.write( "Question 571968: A ball is thrown vertically upward with a speed of 100 mph.
\n" ); document.write( "How long does it take the ball to reach its maximum height? in seconds. What is the ball's maximum height? in meters \n" ); document.write( "
Algebra.Com's Answer #368379 by ankor@dixie-net.com(22740)\"\" \"About 
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A ball is thrown vertically upward with a speed of 100 mph.
\n" ); document.write( "How long does it take the ball to reach its maximum height? in seconds.
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\n" ); document.write( "They want this in meters, convert 100 mph to meters per second
\n" ); document.write( "\"%28100%2A5280%29%2F3600\" * .3048 = 44.7 m/sec
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\n" ); document.write( "Let t = time in sec
\n" ); document.write( "Let h(t) = height at t time
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\n" ); document.write( "h(t) = -4.9t^2 + 44.7t
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\n" ); document.write( "Max occurs at the axis of symmetry: x = -b/(2a)
\n" ); document.write( "t = \"%28-44.7%29%2F%282%2A-4.9%29\"
\n" ); document.write( "t = 4.56 seconds to reach max height
\n" ); document.write( ":
\n" ); document.write( "\"What is the ball's maximum height? in meters\"
\n" ); document.write( "Replace 4.56 sec in the original equation
\n" ); document.write( "h = -4.9(4.56^2) + 44.7(4.56)
\n" ); document.write( "h = -101.9 + 208.8
\n" ); document.write( "h = 101.9 meter max height \n" ); document.write( "
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