document.write( "Question 950791: I need to find the point that is equidistant from (2,6) (-3,1) (8,-6). And I request that you use only formulas instead of drawing graphs. Thank you :) \n" ); document.write( "
Algebra.Com's Answer #580623 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
Assume that this point (a,b) is the center of a circle and the points lie on the circle.
\n" ); document.write( "The circle has equation,
\n" ); document.write( "\"x%5E2%2Bfx%2By%5E2%2Bgy%2Bh=0\"
\n" ); document.write( "Input each point,
\n" ); document.write( "\"4%2B2f%2B36%2B6g%2Bh=0\"
\n" ); document.write( "1.\"2f%2B6g%2Bh=-40\"
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\n" ); document.write( "\"9-3f%2B1%2Bg%2Bh=0\"
\n" ); document.write( "2.\"-3f%2Bg%2Bh=-10\"
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\n" ); document.write( "\"64%2B8f%2B36-6g%2Bh=0\"
\n" ); document.write( "3.\"8f-6g%2Bh=-100\"
\n" ); document.write( "Now subtract eq. 1 from eq. 2 to eliminate \"h\",
\n" ); document.write( "\"-3f%2Bg%2Bh-2f-6g-h=-10%2B40\"
\n" ); document.write( "\"-5f-5g=30\"
\n" ); document.write( "4.\"f%2Bg=-6\"
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\n" ); document.write( "\"8f-6g%2Bh-2f-6g-h=-100%2B40\"
\n" ); document.write( "\"6f-12g=-60\"
\n" ); document.write( "5.\"f-2g=-10\"
\n" ); document.write( "Subtract eq. 4 from eq. 5,
\n" ); document.write( "\"f-2g-f-g=-10-%28-6%29\"
\n" ); document.write( "\"-3g=-4\"
\n" ); document.write( "\"g=4%2F3\"
\n" ); document.write( "Then,
\n" ); document.write( "\"f%2B4%2F3=-6\"
\n" ); document.write( "\"f=-18%2F3-4%2F3\"
\n" ); document.write( "\"f=-22%2F3\"
\n" ); document.write( "and finally,
\n" ); document.write( "\"-3f%2Bg%2Bh=-10\"
\n" ); document.write( "\"22%2B4%2F3%2Bh=-10\"
\n" ); document.write( "\"h=-30%2F3-4%2F3-66%2F3\"
\n" ); document.write( "\"h=-100%2F3\"
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\n" ); document.write( "\"x%5E2-%2822%2F3%29x%2By%5E2%2B%284%2F3%29y-100%2F3=0\"
\n" ); document.write( "So now complete the square to find the center (h,k).
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\n" ); document.write( "\"%28x-11%2F3%29%5E2%2B%28y%2B2%2F3%29%5E2=300%2F9%2B121%2F9%2B4%2F9\"
\n" ); document.write( "\"%28x-11%2F3%29%5E2%2B%28y%2B2%2F3%29%5E2=425%2F9\"
\n" ); document.write( "The center is (\"11%2F3\",\"-2%2F3\").
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