document.write( "Question 1144028: Hi, i just need some help. Find the values of the constant k so that the graph of x^2+y^2+6x-4y=k^2-k-33 is a.) a circle, b.) a single point and c.) an empty set. I found a same problem but i need a whole solution thank you very much \n" ); document.write( "
Algebra.Com's Answer #764987 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2By%5E2%2B6x-4y=k%5E2-k-33\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B6x%29%2B%28y%5E2-4y%29=k%5E2-k-33\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B6x%2B3%5E2%29-3%5E2%2B%28y%5E2-4y%2B2%5E2%29-2%5E2=k%5E2-k-33\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2-9%2B%28y-2%29%5E2-4=k%5E2-k-33\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2%2B%28y-2%29%5E2-13=k%5E2-k-33\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2%2B%28y-2%29%5E2=k%5E2-k-33%2B13\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2%2B%28y-2%29%5E2=k%5E2-k-20\"\r
\n" ); document.write( "\n" ); document.write( "=> it’s a \"circle\" with center at (\"-3\",\"2\") and radius \"sqrt%28k%5E2-k-20%29\"\r
\n" ); document.write( "\n" ); document.write( "so, calculate \"k\": to have real solution find for what value of \"k\"} is \"k%5E2-k-20=0+\"\r
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\n" ); document.write( "\n" ); document.write( "\"k%5E2-k-20=0\".....factor completely\r
\n" ); document.write( "\n" ); document.write( "\"k%5E2%2B4k-5k-20=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28k%5E2%2B4k%29-%285k%2B20%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"k%28k%2B4%29-5%28k%2B4%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28k-5%29%28k%2B4%29=0\"\r
\n" ); document.write( "\n" ); document.write( "solutions:\r
\n" ); document.write( "\n" ); document.write( "\"k=5\" or\"+k=-4\"\r
\n" ); document.write( "\n" ); document.write( "using tese solution we will have radius equal to zero\r
\n" ); document.write( "\n" ); document.write( "then, the graph of \"x%5E2%2By%5E2%2B6x-4y=k%5E2-k-33\" is \r
\n" ); document.write( "\n" ); document.write( "a.) a circle\r
\n" ); document.write( "\n" ); document.write( "if \"k%3E5+\"or \"k%3C-4\"\r
\n" ); document.write( "\n" ); document.write( "or \"k+\"is in interval: (\"-infinity\", \"-4\") and (\"5\", \"infinity\")\r
\n" ); document.write( "\n" ); document.write( "b.) a single point \r
\n" ); document.write( "\n" ); document.write( "if \"k=5\" or \"k=-4\"\r
\n" ); document.write( "\n" ); document.write( "c.) an empty set\r
\n" ); document.write( "\n" ); document.write( "if \"k%3C5\" and \"k%3E-4\" or \"k+\" is in interval \"-4%3Ck%3C5\"\r
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