document.write( "Question 1058712: A projectile is fired upward from the ground with an initial velocity of 76 ft/sec. At the same instant, another projectile is fired upward with an initial velocity of 41 ft/sec from a roof 140 feet above the ground.\r
\n" ); document.write( "\n" ); document.write( "a. After how long will the two projectiles be the same height above the ground?\r
\n" ); document.write( "\n" ); document.write( "b. How high above the ground are the two projectiles at that time?\r
\n" ); document.write( "\n" ); document.write( "Please help thank you! \n" ); document.write( "

Algebra.Com's Answer #673820 by ikleyn(52788) $\"\"$ $\"About$

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\n" ); document.write( "A projectile is fired upward from the ground with an initial velocity of 76 ft/sec. At the same instant, another projectile
\n" ); document.write( "is fired upward with an initial velocity of 41 ft/sec from a roof 140 feet above the ground.\r
\n" ); document.write( "\n" ); document.write( "a. After how long will the two projectiles be the same height above the ground?\r
\n" ); document.write( "\n" ); document.write( "b. How high above the ground are the two projectiles at that time?\r
\n" ); document.write( "\n" ); document.write( "Please help thank you!
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document.write( "1.  An expression for the height (in feet) over the ground level for the first projectile is\r\n" );
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document.write( "     = \r\n" );
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document.write( "    An expression for the height (in feet) over the ground level for the second projectile is\r\n" );
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document.write( "     = .\r\n" );
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\r
\n" ); document.write( "\n" ); document.write( "a) After how long will the two projectiles be the same height above the ground?\r
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document.write( "    It will happen when  = , which gives you an equation\r\n" );
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document.write( "     = .\r\n" );
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document.write( "    Simplify and solve it for t:\r\n" );
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document.write( "    76t - 41t = 140  --->  35t = 140  --->  t =  = 4.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Answer. It will happen in 4 seconds after the launch.\r
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\n" ); document.write( "\n" ); document.write( "b) How high above the ground are the two projectiles at that time?\r
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document.write( "    Simply substitute t=4 into any of the two expressions for , . For example, using , you will get\r\n" );
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document.write( "     = .\r\n" );
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document.write( "    Please complete this calculation on your own.\r\n" );
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\n" ); document.write( "\n" ); document.write( "There is a bunch of similar solved problems in the lessons\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
\n" ); document.write( "\n" ); document.write( "in this site.\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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