document.write( "Question 1040661: Find the equation of the circle if a triangle whose sides lie on the lines 3x+4y=8, 3x-4y=32 and x-8=0 inscribed the circle. \n" ); document.write( "
Algebra.Com's Answer #655550 by Fombitz(32388)\"\" \"About 
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Find the intersection points.
\n" ); document.write( "From eq. 3,
\n" ); document.write( "\"x=8\"
\n" ); document.write( "Substituting into eq. 1,
\n" ); document.write( "\"3%288%29%2B4y=8\"
\n" ); document.write( "\"24%2B4y=8\"
\n" ); document.write( "\"4y=-16\"
\n" ); document.write( "\"y=-4\"
\n" ); document.write( "(8,-4)
\n" ); document.write( "Substituting into eq. 2,
\n" ); document.write( "\"3%288%29-4y=32\"
\n" ); document.write( "\"24-4y=32\"
\n" ); document.write( "\"-4y=8\"
\n" ); document.write( "\"y=-2\"
\n" ); document.write( "(8,-2)
\n" ); document.write( "Finally adding eq. 1 and eq. 2,
\n" ); document.write( "\"3x%2B4y%2B3x-4y=8%2B32\"
\n" ); document.write( "\"6x=40\"
\n" ); document.write( "\"x=40%2F6\"
\n" ); document.write( "\"x=20%2F3\"
\n" ); document.write( "So,
\n" ); document.write( "\"3%2820%2F3%29%2B4y=8\"
\n" ); document.write( "\"20%2B4y=8\"
\n" ); document.write( "\"4y=-12\"
\n" ); document.write( "\"y=-3\"
\n" ); document.write( "(20/3,-3)
\n" ); document.write( "Now you have three points on the circle, solve for the circle.
\n" ); document.write( "Use the general form,
\n" ); document.write( "\"x%5E2%2By%5E2%2BDx%2BEy%2BF=0\"
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "(8,-4):
\n" ); document.write( "\"8%5E2%2B%28-4%29%5E2%2B8D-4E%2BF=0\"
\n" ); document.write( "\"64%2B16%2B8D-4E%2BF=0\"
\n" ); document.write( "4.\"8D-4E%2BF=-80\"
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "(8,-2):
\n" ); document.write( "\"8%5E2%2B%28-2%29%5E2%2B8D-2E%2BF=0\"
\n" ); document.write( "\"64%2B4%2B8D-2E%2BF=0\"
\n" ); document.write( "5.\"8D-2E%2BF=-68\"
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\n" ); document.write( "(20/3,-3):
\n" ); document.write( "\"%2820%2F3%29%5E2%2B%28-3%29%5E2%2B%2820%2F3%29D-3E%2BF=0\"
\n" ); document.write( "\"400%2F9%2B9%2B%2820%2F3%29D-3E%2BF=0\"
\n" ); document.write( "\"400%2B81%2B60D-27E%2B9F=0\"
\n" ); document.write( "6.\"60D-27E%2B9F=-481\"
\n" ); document.write( "Subtracting eq. 5 from eq. 4,
\n" ); document.write( "\"8D-4E%2BF-8D%2B2E-F=-80%2B68\"
\n" ); document.write( "\"-2E=-12\"
\n" ); document.write( "\"E=-6\"
\n" ); document.write( "Substituting into eq. 4,
\n" ); document.write( "\"8D-4%286%29%2BF=-80\"
\n" ); document.write( "7.\"8D%2BF=56\"
\n" ); document.write( "Substituting into eq. 6,
\n" ); document.write( "\"60D-27%286%29%2B9F=-481\"
\n" ); document.write( "8.\"60D%2B9F=-319\"
\n" ); document.write( "Multiply eq. 7 by -9 and add to eq. 8,
\n" ); document.write( "\"-72D-9F%2B60D%2B9F=504-319\"
\n" ); document.write( "\"-12D=185\"
\n" ); document.write( "\"D=-185%2F12\"
\n" ); document.write( "and substituting into eq. 7,
\n" ); document.write( "\"8%28-185%2F12%29%2BF=-56\"
\n" ); document.write( "\"F=-672%2F12%2B1480%2F12\"
\n" ); document.write( "\"F=808%2F12\"
\n" ); document.write( "\"F=202%2F3\"
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "\"x%5E2%2By%5E2-%28185%2F12%29x%2B6y%2B202%2F3=0\"
\n" ); document.write( "You can complete the square to get into center-radius form,
\n" ); document.write( "\"%28x%5E2-%28185%2F12%29x%29%2B%28y%5E2%2B6y%29%2B202%2F3=0\"
\n" ); document.write( "
\n" ); document.write( "\"%28x-185%2F24%29%5E2%2B%28y%2B3%29%5E2=34225%2F576%2B5184%2F576-38784%2F576\"
\n" ); document.write( "\"%28x-185%2F24%29%5E2%2B%28y%2B3%29%5E2=625%2F576\"
\n" ); document.write( "\"%28x-185%2F24%29%5E2%2B%28y%2B3%29%5E2=%2825%2F24%29%5E2\"
\n" ); document.write( "Center : (\"185%2F24\",\"-3\")
\n" ); document.write( "Radius : \"25%2F24\"
\n" ); document.write( ".
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