document.write( "Question 674682: x^2 + y^2 - 4x + 2y = 15\r
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\n" ); document.write( "ii)Show that the point P (4, -5 ) lies in the circle
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Algebra.Com's Answer #419374 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "x^2 + y^2 - 4x + 2y = 15
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document.write( "x^2 - 4x + 4 + y^2 + 2y + 1 = 15 + 4 + 1
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document.write( "  C(2,-1)  r = sqrt(20) = 2sqrt(5)
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document.write( " C(2,-1)
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document.write( "  (4,-5)  m = 4/-2 = -2
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document.write( "tangent Line  m = 1/2
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document.write( " y = (1/2)x + b   ||Using the  (x,y) ordered pair (4,-5) to solve for b
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document.write( "-5 =(1/2)4 + b
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document.write( "-7 = b
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document.write( " y = (1/2)x -7
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