document.write( "Question 1168151: A projectile that is fired vertically into the air with an initial velocity of 120 ft. per second can be modeled by the equation s = 120t - 16t2. In the equation, s is the distance in feet of the projectile above the ground after t seconds.. How long will it take for a projectile to reach 216 feet? Is it possible for the projectile to reach 900 feet? Justify your answer. \n" ); document.write( "

Algebra.Com's Answer #792772 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "To answer the first question, solve the quadratic equation \r\n" );
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document.write( "    120t - 16t^2 = 216.\r\n" );
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document.write( "To answer the second question, consider the quadratic equation\r\n" );
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document.write( "    120t - 16t^2 = 900\r\n" );
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document.write( "and calculate its discriminant.\r\n" );
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document.write( "If the discriminant is non-negative real number, the answer is positive.\r\n" );
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document.write( "If the discriminant is negative real number, the answer is negative.\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
\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( "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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