SOLUTION: solve for x sqrt( x^2 -2x) = x-4

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Question 1118035: solve for x
sqrt( x^2 -2x) = x-4
Found 3 solutions by stanbon, MathTherapy, Alan3354:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve for x
sqrt( x^2 -2x) = x-4
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Square both sides to get:
x^2-2x = x^2-8x+16
x^2 + 6x - 16 = 0
(x+8)(x-2) = 0
x = -8 or x = 2
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Cheers,
Stan H.
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Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

solve for x
sqrt( x^2 -2x) = x-4 
No solutions!

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
solve for x
sqrt(x^2 -2x) = x-4
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solve for x
x^2-2x = x^2-8x+16
-2x = -8x + 16
6x = 16
x = 8/3
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Checking:
--> sqrt%2816%2F9%29+=+-4%2F3, not the principal sqrt