SOLUTION: What is x in the equation: {{{x^2-x-4}}}={{{sqrt(x^2-x-2)}}}

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Question 148082: What is x in the equation:
x%5E2-x-4=sqrt%28x%5E2-x-2%29

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-x-4 = sqrt(x^2-x-2)
Square both sides to get:
x^2 - x -2 = (x^2-(x+4)*(x^2-(x+4))
x^2 - x -2 = x^4 -2x^2(x+4)+(x+4)^2
x^2 -x -2 = x^4 -2x^3-8x^2+x^2+8x+16
x^2 -x -2 = x^4 -2x^3 -7x^2 + 8x + 16
x^4 -2x^3 -8x^2 + 9x + 18 = 0
x=-2 or x = -1.3027756.. or x = 2.3027756 or x = 3
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Cheers,
Stan H.