Question 709801
sqrt(x) - sqrt(x-45) = 3 
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Square both sides to get:
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x - 2sqrt(x^2-45x) + x-45 = 9
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Simplify:
2sqrt(x^2-45x) = 54-2x
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sqrt(x^2-45x) = 27-x
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Square both sides:
x^2-45x = 729-54x+x^2
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9x = 729
x = 81
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Cheers,
Stan H.
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