document.write( "Question 1184838: The ceiling in the hallway 10 m wide is in the shape of a semiellipse and is 9 m
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Algebra.Com's Answer #815483 by Edwin McCravy(20060) $\"\"$ $\"About$

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document.write( "Let's start by drawing the complete ellipse 10 meters wide.\r\n" );
document.write( "Then we'll erase the bottom half and draw in the walls and \r\n" );
document.write( "floor and the places where we want to find the height at \r\n" );
document.write( "(2 meters from the walls).\r\n" );
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document.write( "Since it's:\r\n" );
document.write( ">>>9 m high in the center and 6 m high at the side wall.<<<\r\n" );
document.write( "we know that the upper covertex is 3 meters higher than the \r\n" );
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document.write( "a = 5, b = 3, so the equation of the whole ellipse\r\n" );
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document.write( "Now we'll erase the bottom half of the ellipse, draw in\r\n" );
document.write( "the walls.  The floor is 6m below the vertices, so the\r\n" );
document.write( "walls go down to the points (±5,-6). We'll draw the heights\r\n" );
document.write( "in green 2m from the walls:\r\n" );
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document.write( "2 meters from the wall is 3 meters from the center so we\r\n" );
document.write( "first substitute x=3 in the ellipse's equation to see how \r\n" );
document.write( "high above the top of the wall the ellipse is there.\r\n" );
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document.write( "Multiply through by 225\r\n" );
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document.write( "We erased the negative value, so\r\n" );
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document.write( "Then we add 6 meters to get the height from the floor.\r\n" );
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document.write( "Answer: 8.4 meters.\r\n" );
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document.write( "Edwin

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