document.write( "Question 1142113: Find the coordinates of the
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Algebra.Com's Answer #762780 by ikleyn(52788)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "            In your post, (a) is not an equation at all.\r
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\n" ); document.write( "\n" ); document.write( "            (e) is not an equation of an ellipse. It represents the single point (0,0), which is the origin of the coordinate system.\r
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\n" ); document.write( "\n" ); document.write( "            Your equation (g) looks suspicious.\r
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\n" ); document.write( "\n" ); document.write( "            I will do (c), (d) and (f) for you.\r
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\n" ); document.write( "\n" ); document.write( "In order to understand my solution, you need to be familiar with the basic notions and formulas related to ellipses.\r
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\n" ); document.write( "\n" ); document.write( "It is the NECESSARY condition to understand what is written in my post.\r
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\n" ); document.write( "\n" ); document.write( "You can learn all the necessary introductory knowledge from my lessons\r
\n" ); document.write( "\n" ); document.write( "    - Ellipse definition, canonical equation, characteristic points and elements \r
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document.write( "(c)  \"%28y%5E2%29%2F18\" + \"%28x%5E2%29%2F9\" = 1\r\n" );
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document.write( "     It is the standard form of an ellipse equation.\r\n" );
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document.write( "     Moreover, it is the canonical form of an ellipse equation.\r\n" );
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document.write( "     The ellipse, described by this equation, has the center at the point (0,0), which is the origin of the coordinate system.\r\n" );
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document.write( "     The major axis of this ellipse is VERTICAL axis \"y\", while the minor axis is HORIZONTAL axis \"x\".\r\n" );
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document.write( "         This ellipse IS TALLER than WIDE.\r\n" );
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document.write( "     The major semi-axis has the length of \"sqrt%2818%29\" = \"3%2Asqrt%282%29\" units,\r\n" );
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document.write( "     while the minor semi-axis has the length of \"sqrt%289%29\" = 3 units.\r\n" );
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document.write( "     Therefore, the major axis has the length of  \"6%2Asqrt%282%29\" units, while the minor axis has the length of  6 units.\r\n" );
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document.write( "(d)  \"4x%5E2\" + \"8y%5E2\" = 32.\r\n" );
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document.write( "     Divide both sides of this equation by 32.  You will get an equivalent equation\r\n" );
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document.write( "     \"x%5E2%2F8\" + \"y%5E2%2F4\" = 1.\r\n" );
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document.write( "     It is the standard form of an ellipse equation.\r\n" );
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document.write( "     Moreover, it is the canonical form of an ellipse equation.\r\n" );
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document.write( "     The ellipse, described by this equation, has the center at the point (0,0), which is the origin of the coordinate system.\r\n" );
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document.write( "     The major axis of this ellipse is horizontal x-axis, while the minor axis is vertical y-axis.\r\n" );
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document.write( "     The major semi-axis has the length of \"sqrt%288%29\" = \"2%2Asqrt%282%29\" units,\r\n" );
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document.write( "     while the minor semi-axis has the length of \"sqrt%284%29\" = 2 units.\r\n" );
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document.write( "     Therefore, the major axis has the length of  \"4%2Asqrt%282%29\" units, while the minor axis has the length of  4 units.\r\n" );
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document.write( "(f)  \"%28y%2B11%29%5E2%2F144\" + \"%28x-5%29%5E2%2F121\" = 1.    <<<---=== Notice that your original equation was written INCORRECTLY, and I fixed it (!)\r\n" );
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document.write( "     Your equation is\r\n" );
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document.write( "     \"%28y%2B11%29%5E2%2F12%5E2\" + \"%28x-5%29%5E2%2F11%5E2\" = 1.\r\n" );
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document.write( "     It is the standard form of an ellipse equation.\r\n" );
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document.write( "     ( But not its canonical form ).\r\n" );
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document.write( "     The ellipse, described by this equation, has the center at the point (5,-11) of the coordinate system.\r\n" );
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document.write( "     The major axis of this ellipse is VERTICAL line parallel to y-axis, while the minor axis is the HORIZONTAL line parallel to x-axis.\r\n" );
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document.write( "         This ellipse IS TALLER than WIDE.\r\n" );
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document.write( "     The major semi-axis has the length of 12 units,\r\n" );
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document.write( "     while the minor semi-axis has the length of  11 units.\r\n" );
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document.write( "     Therefore, the major axis has the length of  24 units, while the minor axis has the length of  22 units.\r\n" );
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