document.write( "Question 1145770: A model rocket is launched with an initial upward velocity of 50 m/s. The rockets height “h@ (in meters) after “t” seconds is given by the following.
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\n" ); document.write( "Find all values of “t” for which the Rockets height is 20 meters
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Algebra.Com's Answer #767017 by ikleyn(52817)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "These values of t are the roots of the equation\r\n" );
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document.write( "    H(t) = 20,  which is  -5t^2 + 50t = 20.\r\n" );
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document.write( "Write it in the standard form\r\n" );
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document.write( "    5t^2 - 50t + 20 = 0.\r\n" );
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document.write( "Solve it using the quadratic formula.\r\n" );
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document.write( "The two roots will be your answers.\r\n" );
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document.write( "The problem has two answers: one for for the model moving up and another for the model falling down.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Having my instructions, you do the rest.\r
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\n" ); document.write( "\n" ); document.write( "If you still have questions or problems with it, then let me know.\r
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\n" ); document.write( "Comment from student: Thank u. I got 0.42 and 9.58. Is that correct ?
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\n" ); document.write( "\n" ); document.write( "My response :   YES  (!)  It is  CORRECT  (!)\r
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\n" ); document.write( "\n" ); document.write( "Nice job !\r
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\n" ); document.write( "\n" ); document.write( "As my reward and a bonus to you for your nice job, here is the list of my lessons in this site related to similar problems\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.
\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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