document.write( "Question 452048: When a ball is thrown, its height in feet h after t seconds is given by the equation \r
\n" ); document.write( "\n" ); document.write( "h=vt-16t^2\r
\n" ); document.write( "\n" ); document.write( "where v is the initial upwards velocity in feet per second. If v=19 feet per second, find all values of t for which h=5 feet. Do not round any intermediate steps. Round your answer to 2 decimal places.\r
\n" ); document.write( "\n" ); document.write( "t= ? seconds\r
\n" ); document.write( "\n" ); document.write( "Could there be more than one answer? If so, what are all answers? \n" ); document.write( "

Algebra.Com's Answer #310751 by htmentor(1343) $\"\"$ $\"About$

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When a ball is thrown, its height in feet h after t seconds is given by the equation \r
\n" ); document.write( "\n" ); document.write( "h=vt-16t^2 -> -16t^2 + vt - h = 0\r
\n" ); document.write( "\n" ); document.write( "Given: v=19 fps
\n" ); document.write( "Find all values of t for which h=5 ft.\r
\n" ); document.write( "\n" ); document.write( "We need to solve the quadratic equation for t:
\n" ); document.write( "-16t^2 + 19t - 5 = 0
\n" ); document.write( "t = (-19 +- sqrt(19^2 -4(16)(5)))/-32
\n" ); document.write( "This gives t = 0.39, 0.79
\n" ); document.write( "So the two times are t = 0.39 s and 0.79 s.
\n" ); document.write( "The graph of the ball's trajectory is below:
\n" ); document.write( " $\"graph%28300%2C300%2C-3%2C3%2C-6%2C6%2C-16x%5E2%2B19x%29\"$ \n" ); document.write( "

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