document.write( "Question 1188744: A ball is dropped from the top of a 256-foor cliff. The height of the stone about the ground t seconds after being dropped is h = 16t2 + 256 in feet. Find the amount of time it takes for the stone to hit the ground. \n" ); document.write( "

Algebra.Com's Answer #819909 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " In your post, the equation for the height is written INCORRECTLY.\r
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\n" ); document.write( "\n" ); document.write( " The correct form is h = -16t^2 + 256 feet.\r
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document.write( "Find time \"t\" from this quadratic equation\r\n" );
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document.write( "    -16t^2 + 256 = 0    (level of the ground)\r\n" );
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document.write( "To solve, factor the equation\r\n" );
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document.write( "    -16(t^2 - 16) = 0\r\n" );
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document.write( "to make its root clearly visible  t^2 = 16,   = - = 4,   =  = 4.\r\n" );
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document.write( "Of the two roots, only positive t = 4 works as the solution to the problem.\r\n" );
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document.write( "ANSWER.  4 seconds.\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
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\n" ); document.write( "\n" ); document.write( "Consider these lessons as your textbook, handbook, tutorials and (free of charge) home teacher.
\n" ); document.write( "Read them attentively and learn how to solve this type of problems once and for all.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook under the topic \"Projectiles launched/thrown and moving vertically up and dawn\".\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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