document.write( "Question 1083554: The point p(3,-4) lies ..........the circle X^2+y^2+6x+8y=0
\n" ); document.write( "a) inside
\n" ); document.write( "b) outside
\n" ); document.write( "c)on
\n" ); document.write( "d)none
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Algebra.Com's Answer #697563 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Answer: Choice B) outside
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\n" ); document.write( "\n" ); document.write( "Explanation:\r
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\n" ); document.write( "\n" ); document.write( "The point (3,-4) is equal to (x,y).
\n" ); document.write( "(x,y) = (3,-4)
\n" ); document.write( "The x coordinate is x = 3
\n" ); document.write( "The y coordinate is y = -4\r
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\n" ); document.write( "\n" ); document.write( "Plug x = 3 and y = -4 into the the equation x^2+y^2+6x+8y=0 and simplify.\r
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\n" ); document.write( "\n" ); document.write( "x^2+y^2+6x+8y=0
\n" ); document.write( "(3)^2+(-4)^2+6(3)+8(-4)=0
\n" ); document.write( "9+16+6(3)+8(-4)=0
\n" ); document.write( "9+16+18-32=0
\n" ); document.write( "25+18-32=0
\n" ); document.write( "33-32=0
\n" ); document.write( "1=0\r
\n" ); document.write( "\n" ); document.write( "The last equation (1 = 0) is false.
\n" ); document.write( "So the point is NOT on the boundary of the circle.\r
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\n" ); document.write( "\n" ); document.write( "The left side result is larger than 0, telling us that the point P is going to be on the outside of the circle. \r
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\n" ); document.write( "\n" ); document.write( "If we got a negative result on the left side, then P would be on the inside of the circle.\r
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\n" ); document.write( "\n" ); document.write( "Visual Proof:
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\n" ); document.write( "(Image generated by GeoGebra which is free graphing software)
\n" ); document.write( "Note: The equation \"x%5E2%2By%5E2%2B6x%2B8y=0\" is equivalent to \"%28x%2B3%29%5E2%2B%28y%2B4%29%5E2+=+25\"
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