document.write( "Question 278068: i'm learning about ellipses and i have the problem:
\n" ); document.write( "x squared+4y squared-6x+24y+41=0
\n" ); document.write( "i need to find the center, foci, and vertices.
\n" ); document.write( "i have no idea how to even start, i tried by first completing the square but i'm missing something because i get confused by that 41 that is thrown in there, please help.
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Algebra.Com's Answer #202462 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
i'm learning about ellipses and i have the problem:
\n" ); document.write( "x squared+4y squared-6x+24y+41=0
\n" ); document.write( "i need to find the center, foci, and vertices.
\n" ); document.write( "i have no idea how to even start, i tried by first completing the square but i'm missing something because i get confused by that 41 that is thrown in there, please help.
\n" ); document.write( "
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document.write( "\"x%5E2%2B4y%5E2-6x%2B24y%2B41=0\"\r\n" );
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document.write( "Get the number on the right by adding \"-41\" to both sides:\r\n" );
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document.write( "\"x%5E2%2B4y%5E2-6x%2B24y=-41\"\r\n" );
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document.write( "Swap the two middle terms to get the \"x\"-term next to the \"x%5E2\"-term\r\n" );
document.write( "\"x%5E2-6x%2B4y%5E2%2B24y=-41\"\r\n" );
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document.write( "Multiply the coefficient of x, which is \"-6\", by \"1%2F2\",\r\n" );
document.write( "get \"-3\" then square that number \"%28-3%29%5E2\" which \r\n" );
document.write( "gives \"red%28%22%2B9%22%29\"\r\n" );
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document.write( "Now add \"red%28%22%2B9%22%29\" to both sides:\r\n" );
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document.write( "\"x%5E2-6x%2Bred%289%29%2B4y%5E2%2B24y=-41%2Bred%289%29\"\r\n" );
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document.write( "Since the \"y%5E2\" term has a coefficient other than 1,\r\n" );
document.write( "factor the 4 out of the last two terms on the left:\r\n" );
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document.write( "\"x%5E2-6x%2Bred%289%29%2B4%28y%5E2%2B6y%29=-41%2Bred%289%29\"\r\n" );
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document.write( "Now we complete the square inside the parentheses.\r\n" );
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document.write( "Multiply the coefficient of y, which is \"6\", by \"1%2F2\",\r\n" );
document.write( "get \"3\" then square that number \"3%5E2\" which \r\n" );
document.write( "gives \"green%28%22%2B9%22%29\"\r\n" );
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document.write( "Now we add \"green%28%22%2B9%22%29\" inside the parentheses.  However\r\n" );
document.write( "when we add \"%22%2B9%22\" inside the parentheses we are REALLY\r\n" );
document.write( "adding \"4%2Agreen%28%22%2B9%22%29\" or \"green%28%22%2B36%22%29\" to the left side \r\n" );
document.write( "because everything in the parentheses is multiplied by the \"4\"\r\n" );
document.write( "in front of the parentheses.  So we add \"%22%2B36%22\" to the right side:\r\n" );
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document.write( "\"x%5E2-6x%2Bred%289%29%2B4%28y%5E2%2B6y%2Bgreen%289%29%29=-41%2Bred%289%29%2Bgreen%2836%29\"\r\n" );
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document.write( "Now we factor the first three terms as \"%28x-3%29%28x-3%29\" or \"%28x-3%29%5E2\"\r\n" );
document.write( "and we factor the three terms inside the parentheses as \"%28y%2B3%29%28y%2B3%29\"\r\n" );
document.write( "or \"%28y%2B3%29%5E2\", and combine the numbers on the right as \"4\"\r\n" );
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document.write( "\"%28x-3%29%5E2%2B4%28y%2B3%29%5E2=4\"\r\n" );
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document.write( "Now to get 1 on the right we divive every term through by 4\r\n" );
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document.write( "\"%28x-3%29%5E2%2F4%2B4%28y%2B3%29%5E2%2F4=4%2F4\"\r\n" );
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document.write( "\"%28x-3%29%5E2%2F4%2B%28y%2B3%29%5E2%2F1=1\"\r\n" );
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document.write( "Notice that I left a 1 under the bottom of the second term\r\n" );
document.write( "so that it would be in standard form\r\n" );
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document.write( "Since \"4\" is larger than \"1\" and the larger term is under\r\n" );
document.write( "the \"%28x-h%29%5E2\" term it is in the form\r\n" );
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document.write( "\"%28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1\" \r\n" );
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document.write( "and has its major axis horizontal.\r\n" );
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document.write( "\"h=3\", \"k=-3\", \"a%5E2=4\", so \"a=2\"\r\n" );
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document.write( "\"b%5E2=1\", so \"b=1\", so we plot the center {3,-3)\r\n" );
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document.write( "Then we draw the major axis by drawing a horizontal line \"a=2\"\r\n" );
document.write( "units both right and left of the center (3,-3)\r\n" );
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document.write( "Now we can get the vertices, for they are the points ar the ends\r\n" );
document.write( "of the major axis, and we can see that the major axis, the green\r\n" );
document.write( "line segment starts at (1,-3) on the left and goes to (5,-3) on\r\n" );
document.write( "the right, so the vertices are\r\n" );
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document.write( "(1,-3) and (5,-3)\r\n" );
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document.write( "Now we draw the minor axis by drawing a horizontal line \"b=1\"\r\n" );
document.write( "units both up and down from the center (3,-3):\r\n" );
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document.write( "Now we can sketch in the ellipse:\r\n" );
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document.write( "Finally we need to find the foci.  The distance from\r\n" );
document.write( "the center to each focus is \"c\" and \"c\" is\r\n" );
document.write( "calculated by this Pythagorean identity:\r\n" );
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document.write( "\"c%5E2=a%5E2-b%5E2\"\r\n" );
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document.write( "\"c%5E2=2%5E2-1%5E2\"\r\n" );
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document.write( "\"c%5E2=4-1\"\r\n" );
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document.write( "\"c=sqrt%283%29\"\r\n" );
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document.write( "The coordinates of the foci are\r\n" );
document.write( "points which are distance of \"sqrt%283%29\"\r\n" );
document.write( "units right and left of the center on the major axis,\r\n" );
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document.write( "so the two foci are these points: \r\n" );
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document.write( "(3-Ö3,-3) and (3+Ö3,-3)\r\n" );
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document.write( "They are plotted below:\r\n" );
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document.write( "Edwin
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