document.write( "Question 1206162: In a video game, a bird is flung on a sling shot and follows a parabolic path. The path of the bird can be modeled by the equation h=-16t^2+55t+50 , where h
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Algebra.Com's Answer #843415 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "In a video game, a bird is flung on a sling shot and follows a parabolic path.
\n" ); document.write( "The path of the bird can be modeled by the equation h=-16t^2+55t+50 , where h
\n" ); document.write( "is the height of the bird and t is the amount of time, in seconds, the bird has been in the air.
\n" ); document.write( "How long will it take the bird to reach a height of 40 feet in the air
\n" ); document.write( "for the first time? Round your answer to the nearest hundredth.
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document.write( "From the equation, the bird starts at height of 50 feet\r\n" );
document.write( "and moves up under gravitation at the initial vertical speed of 55 ft/s up; \r\n" );
document.write( "then it falls down like a stone, under gravitation.\r\n" );
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document.write( "In short words, solve this quadratic equation\r\n" );
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document.write( "    -16t^2 + 55t + 50 = 40\r\n" );
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document.write( "using the quadratic formula, and take its greatest root.\r\n" );
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document.write( "    +-------------------------------------------------------------+\r\n" );
document.write( "    |  We take the greatest root, because, as I described above,  |\r\n" );
document.write( "    |    when the bird is at the height 40 ft first time,         |\r\n" );
document.write( "    |          it is at this height last time.                    |\r\n" );
document.write( "    +-------------------------------------------------------------+\r\n" );
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document.write( "The answer is t =  = 1.96 seconds (rounded).\r\n" );
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\n" ); document.write( "\n" ); document.write( "In this site, there is a bunch of lessons on a projectile thrown/shot/launched vertically up\r
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\n" ); document.write( "\n" ); document.write( "    - Introductory lesson on a projectile thrown-shot-launched vertically up \r
\n" ); document.write( "\n" ); document.write( "    - Problem on a projectile moving vertically up and down\r
\n" ); document.write( "\n" ); document.write( "    - Problem on an arrow shot vertically upward\r
\n" ); document.write( "\n" ); document.write( "    - Problem on a ball thrown vertically up from the top of a tower \r
\n" ); document.write( "\n" ); document.write( "    - Problem on a toy rocket launched vertically up from a tall platform\r
\n" ); document.write( "\n" ); document.write( "    - A flare is launched from a life raft vertically up \r
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\n" ); document.write( "\n" ); document.write( "Consider these lessons as your textbook, handbook, tutorials and (free of charge) home teacher.
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