document.write( "Question 1204202: 36x^2+25y^2-288x+200y+76=0 is the equation of a conic. Write the standard form of that conic. \n" ); document.write( "
Algebra.Com's Answer #840297 by Edwin McCravy(20060)\"\" \"About 
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document.write( "\"36x%5E2%2B25y%5E2-288x%2B200y%2B76=0\"\r\n" );
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document.write( "Get the x terms together and the y-terms together and\r\n" );
document.write( "the constant term on the right\r\n" );
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document.write( "\"36x%5E2-288x%2B25y%5E2%2B200y=-76\"\r\n" );
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document.write( "Factor the coefficient of the squared terms out of the first two terms\r\n" );
document.write( "and the last two terms on the left:\r\n" );
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document.write( "\"36%28x%5E2-8x%29%2B25%28y%5E2%2B8y%29=-76\"\r\n" );
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document.write( "We want to add a positive number inside each parentheses to make\r\n" );
document.write( "it factorable as a perfect square.  To find that number\r\n" );
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document.write( "In the first parentheses,\r\n" );
document.write( "Half the coefficient of x, which is -8, getting -4, then square\r\n" );
document.write( "-4 getting +16 and add that inside the first parentheses on the right. Since \r\n" );
document.write( "there is a coefficient of 36, adding +16 inside the first parentheses is\r\n" );
document.write( "the equivalent of adding 36x16 or 576 to the left side. So we must add\r\n" );
document.write( "576 to the right side as well:\r\n" );
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document.write( "\"36%28x%5E2-8x%2B16%29%2B25%28y%5E2%2B8y%29=-76%2B576\"\r\n" );
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document.write( "In the second parentheses,\r\n" );
document.write( "Half the coefficient of y, which is +8, getting +4, then square\r\n" );
document.write( "+4 getting +16 and add that inside the second parentheses on the right. Since \r\n" );
document.write( "there is a coefficient of 25, adding +16 inside the second parentheses is\r\n" );
document.write( "the equivalent of adding 25x16 or 400 to the left side. So we must add\r\n" );
document.write( "400 to the right side as well:\r\n" );
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document.write( "\"36%28x%5E2-8x%2B16%29%2B25%28y%5E2%2B8y%2B16%29=-76%2B576%2B400\"\r\n" );
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document.write( "Now we factor each parentheses and combine the numbers on the right side.\r\n" );
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document.write( "\"36%28x-4%29%28x-4%29%2B25%28y%2B4%29%28y%2B4%29=900\"\r\n" );
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document.write( "We notice that they factored into perfect squares, so perhaps you can skip\r\n" );
document.write( "the preceding step, and have gone straight to\r\n" );
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document.write( "\"36%28x-4%29%5E2%2B25%28y%2B4%29%5E2=900\"\r\n" );
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document.write( "Now we must get 1 on the right side, so we divide through by 900\r\n" );
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document.write( "The coefficients of the squares of binomials must be 1, so divide\r\n" );
document.write( "the top and bottom of the first term by 36 and the second by 25.\r\n" );
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document.write( "\"%28x-4%29%5E2%2F25%5E%22%22%2B%28y%2B4%29%5E2%2F36%5E%22%22=1\"\r\n" );
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document.write( "\"%28x-4%29%5E2%2F5%5E2%2B%28y%2B4%29%5E2%2F6%5E2=1\" compare to \"%28x-h%29%5E2%2Fb%5E2%2B%28y-k%29%5E2%2Fa%5E2=1\"\r\n" );
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document.write( "That's a vertical ellipse (looks like the number \"0\") because the larger\r\n" );
document.write( "denominator a2 is under the term in y.  \r\n" );
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document.write( "It has center (h,k)=(4,-4). \r\n" );
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document.write( "It has semi-major axis a=6, semi-minor axis b=5.\r\n" );
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document.write( "Vertices (4,-10) and (4,2) and co-vertices (-1,-4) and (9,-4).\r\n" );
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document.write( "Edwin
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