document.write( "Question 196705: I cannot seem to find the correct standard equation, foci, and asymptotes of the following hyperbola:
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Algebra.Com's Answer #147433 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
I cannot seem to find the correct standard equation, foci, and asymptotes of the following hyperbola:\r
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document.write( "Rearrange so that the two terms in x are next to\r\n" );
document.write( "each other and the two terms in y are next to\r\n" );
document.write( "each other, and 11 to both sides:\r\n" );
document.write( "sides:\r\n" );
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document.write( "\"x%5E2-6x-4y%5E2-16y=11\"\r\n" );
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document.write( "The coefficient of \"x%5E2\" is already 1, so\r\n" );
document.write( "we don't factor anything out of it, just enclose the\r\n" );
document.write( "first two terms in parentheses:\r\n" );
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document.write( "\"%28x%5E2-6x%29-4y%5E2-16y=11\"\r\n" );
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document.write( "Now factor only -4 (not y) out of the last two terms\r\n" );
document.write( "on the left.\r\n" );
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document.write( "\"%28x%5E2-6x%29-4%28y%5E2%2B4y%29=11\"\r\n" );
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document.write( "Complete the square in each parentheses.  \r\n" );
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document.write( "In the first parentheses multiply the \"-6\" coefficient of\r\n" );
document.write( "x by \"1%2F2\", getting \"-3\".  Then we square \"-3\",\r\n" );
document.write( "getting \"%28-3%29%5E2=9\".  So we add 9 to both sides:\r\n" );
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document.write( "\"%28x%5E2-6x%2B9%29-4%28y%5E2%2B4y%29=11%2B9\"\r\n" );
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document.write( "\"%28x%5E2-6x%2B9%29-4%28y%5E2%2B4y%29=20\"\r\n" );
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document.write( "Now we factor the first parentheses as \"%28x-3%29%28x-3%29\"\r\n" );
document.write( "or \"%28x-3%29%5E2\"\r\n" );
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document.write( "\"%28x-3%29%5E2-4%28y%5E2%2B4y%29=20\"\r\n" );
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document.write( "In the second parentheses multiply the \"4\" coefficient of\r\n" );
document.write( "y by \"1%2F2\", getting \"2\".  Then we square \"2\",\r\n" );
document.write( "getting \"%282%29%5E2=4\".  So we add 4 inside the second\r\n" );
document.write( "parentheses.\r\n" );
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document.write( "But since there is a \"-4\" factor in front of the second\r\n" );
document.write( "parentheses, when we add \"4\" inside the second parentheses\r\n" );
document.write( "we are really adding \"-4\" times \"4\" or \"-16\" to the\r\n" );
document.write( "left side, so we must add \"-16\" to the right side too.\r\n" );
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document.write( "\"%28x-3%29%5E2-4%28y%5E2%2B4y%2B4%29=20-16\"\r\n" );
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document.write( "\"%28x-3%29%5E2-4%28y%5E2%2B4y%2B4%29=4\"\r\n" );
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document.write( "Now we factor the second parentheses as \"%28y%2B2%29%28y%2B2%29\"\r\n" );
document.write( "or \"%28y%2B2%29%5E2\"\r\n" );
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document.write( "\"%28x-3%29%5E2-4%28y%2B2%29%5E2=4\"\r\n" );
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document.write( "Next we get a \"1\" on the right side by dividing\r\n" );
document.write( "through by \"4\"\r\n" );
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document.write( "\"%28%28x-3%29%5E2%29%2F4-4%28y%2B2%29%5E2%2F4=4%2F4\"\r\n" );
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document.write( "\"%28%28x-3%29%5E2%29%2F4-4%28y%2B2%29%5E2%2F4=1\"\r\n" );
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document.write( "Now to get rid of the 4 on top on the second term, we\r\n" );
document.write( "divide top and bottom by 4\r\n" );
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document.write( "\"%28%28x-3%29%5E2%29%2F4-%28%284%28y%2B2%29%5E2%29%2F4%29%2F%284%2F4%29=1\"\r\n" );
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document.write( "\"%28%28x-3%29%5E2%29%2F4-%28%28cross%284%29%28y%2B2%29%5E2%29%2Fcross%284%29%29%2F1=1\"\r\n" );
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document.write( "\"%28%28x-3%29%5E2%29%2F4-%28%28y%2B2%29%5E2%29%2F1=1\"\r\n" );
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document.write( "Can you go from here? \r\n" );
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document.write( "Compare to\r\n" );
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document.write( "\"%28%28x-h%29%5E2%29%2Fa%5E2-%28%28y-k%29%5E2%29%2Fb%5E2=1\"\r\n" );
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document.write( "So \"h=3\", \"k=-2\", \"a=2\", \"b=1\"\r\n" );
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document.write( "So center = (h,k) = (3,-2)\r\n" );
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document.write( "The two vertices are a=2 units left and right of the\r\n" );
document.write( "center, so they are (1,-2) and (5,-2)\r\n" );
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document.write( "The two foci are \"c\" units left and right of the center.\r\n" );
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document.write( "First we calculate \"c\" using\r\n" );
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document.write( "\"c%5E2=a%5E2%2Bb%5E2\"\r\n" );
document.write( "\"c%5E2=2%5E2%2B1%5E2\"\r\n" );
document.write( "\"c%5E2=4%2B1\"\r\n" );
document.write( "\"c%5E2=5\"\r\n" );
document.write( "\"c=sqrt%285%29\"\r\n" );
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document.write( "So the two foci are \"c=sqrt%285%29\" units left and right of the\r\n" );
document.write( "center, so they are (\"3-sqrt%285%29\",-2) and (\"3%2Bsqrt%285%29\",-2)\r\n" );
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document.write( "The asymptotes have slopes which are ±\"b%2Fa\" or\r\n" );
document.write( "±\"1%2F2\"\r\n" );
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document.write( "And the go through the center (3,-2), so we use the\r\n" );
document.write( "point slope formula:\r\n" );
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document.write( "For the asymptote that has slope \"1%2F2\":\r\n" );
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document.write( "\"y%2B2=%281%2F2%29%28x-3%29\"\r\n" );
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document.write( "Multiply both sides by 2\r\n" );
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document.write( "\"2y%2B4=x-3\"\r\n" );
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document.write( "\"-x%2B2y=-7\"\r\n" );
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document.write( "\"x-2y=7\"\r\n" );
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document.write( "---------------\r\n" );
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document.write( "For the asymptote that has slope \"-1%2F2\":\r\n" );
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document.write( "\"y%2B2=%28-1%2F2%29%28x-3%29\"\r\n" );
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document.write( "Multiply both sides by -2\r\n" );
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document.write( "\"-2y-4=x-3\"\r\n" );
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document.write( "\"-x-2y=1\"\r\n" );
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document.write( "\"x%2B2y=-1\"\r\n" );
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document.write( "Edwin
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