SOLUTION: x-3 square root of x -4=0 I could not find the square root symbol on my keyboard

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Question 743641: x-3 square root of x -4=0
I could not find the square root symbol on my keyboard
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
x-3 square root of x -4=0
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x - 3sqrt(x) - 4 = 0
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3sqrt(x) = x-4
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Square both sides to get:
9x = x^2 - 8x + 16
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x^2 -17x + 16 = 0
Factor:
(x-1)(x-16) = 0
x = 1 or x = 16
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Check for extraneous solutions:
x - 3sqrt(x) - 4 = 0
Test x= 1
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1 - 3 - 4 = 0 :::: false
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Test x = 16
16 - 3*4 - 4 = 0
16 - 16 = 0 ::::: true
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Colclusion: x = 16
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Cheers,
Stan H.