document.write( "Question 1137871: A rocket is shot into the air and travels h = −4.9t^2 +30t + 45 where h is the height of the object and t is in seconds. What is the time when the object hits the ground to the nearest tenth of a second? \n" ); document.write( "
Algebra.Com's Answer #755742 by ikleyn(52781)\"\" \"About 
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document.write( "It will happen when h(t) = 0.\r\n" );
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document.write( "To determine this time moment, you need to solve this quadratic equation\r\n" );
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document.write( "    -4.9t^2 + 30t + 45 = 0.\r\n" );
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document.write( "I will leave the solution to you.\r\n" );
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\n" ); document.write( "\n" ); document.write( "If you want to see many similar solved problems and to have them as your templates,  look into the lessons\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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