document.write( "Question 1185590: A flare is launched from a life raft an initial velocity of 80 meters per second. How many
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Algebra.Com's Answer #816414 by ikleyn(52778)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "A flare is launched from a life raft \"highlight%28vertically_up%29\" \"cross%28an%29\" at initial velocity of 80 meters per second.
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\n" ); document.write( "\n" ); document.write( "            As it was written in the post,  the condition was  INCOMPLETE,  since the direction of the launch was not specified.\r
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\n" ); document.write( "\n" ); document.write( "            THEREFORE,  I edited your post in order for the post would be meaningful.\r
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document.write( "The function describing the height of this launched object (in meters over the sea level) versus time is\r\n" );
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document.write( "    h(t) = -5t^2 + 80t.\r\n" );
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document.write( "To find the time it takes the flare to fall back and to get the sea level is\r\n" );
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document.write( "    h(t) = 0,   or   -5t^2 + 80t = 0.\r\n" );
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document.write( "We factor it\r\n" );
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document.write( "     5t(16-t) = 0\r\n" );
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document.write( "and find two roots  t= 0  and  t= 16.\r\n" );
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document.write( "First root is not interesting for us (it describes the starting moment).\r\n" );
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document.write( "The other root, t= 16 seconds, is the solution to the problem.\r\n" );
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document.write( "ANSWER.  The flare will fall back to the sea in 16 seconds.\r\n" );
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\n" ); document.write( "\n" ); document.write( "To see many other solved similar and different problems and to learn the subject deeper,  wider and better,  see the lessons\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.
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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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