document.write( "Question 1006752: A ball is thrown upward with an initial velocity of 28 meters per second from a cliff that is high. The height of the ball is given by the quadratic equation where h is in meters and t is the time in seconds since the ball was thrown. Find the time it takes the ball to hit the ground. Round your answer to the nearest tenth of a second. \n" ); document.write( "
Algebra.Com's Answer #622849 by ankor@dixie-net.com(22740)\"\" \"About 
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A ball is thrown upward with an initial velocity of 28 meters per second from a cliff that is high.
\n" ); document.write( " The height of the ball is given by the quadratic equation where h is in meters and t is the time in seconds since the ball was thrown.
\n" ); document.write( " Find the time it takes the ball to hit the ground.
\n" ); document.write( " Round your answer to the nearest tenth of a second.
\n" ); document.write( ":
\n" ); document.write( "Using the gravitational force of 4.9 m/sec/sec, assume the cliff is 210 meters high
\n" ); document.write( ":
\n" ); document.write( "Gravity pulls downward -, initial velocity is upward +
\n" ); document.write( "h = -4.9t^2 + 28t + 210
\n" ); document.write( "when hits the ground, h = 0
\n" ); document.write( "-4.9t^2 + 28t + 210 = 0
\n" ); document.write( "solve this equation using the quadratic formula a=-4.9; b=28; c=210
\n" ); document.write( "I got a positive solution of t = 10 secs to hit the ground
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