document.write( "Question 1181132: A ball leaves the end of a baseball bat and travels according to the formula h(t) = -16t² + 64t where h is the height of the ball in feet and t is the time in seconds. How many seconds will it take for the ball to reach a height of 64ft in the air?
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Algebra.Com's Answer #810965 by ikleyn(52781)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "To answer the question, you need to solve this quadratic equation\r\n" );
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document.write( "    h(t) = 0,\r\n" );
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document.write( "or\r\n" );
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document.write( "    -16t^2 + 64t = 64.\r\n" );
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document.write( "So, simplify the equation\r\n" );
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document.write( "    t^2 - 4t + 4 = 0\r\n" );
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document.write( "    \"%28t-2%29%5E2\" = 0\r\n" );
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document.write( "and find the root  t = 2.\r\n" );
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document.write( "ANSWER.  In 2 seconds, the height will be 64 feet.\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( "    - 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.
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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
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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( "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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