SOLUTION: {{{ sqrt(2x-5)=x-4 }}}

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Question 1130036: ++sqrt%282x-5%29=x-4+++
Found 2 solutions by josgarithmetic, stanbon:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
%28sqrt%282x-5%29%29%5E2=%28x-4%29%5E2
2x-5=x%5E2-8x%2B16
x%5E2-10x%2B21=0
%28x-7%29%28x-3%29=0




Best answer,
x=7

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt(2x-5)=x-4
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Square both sides to get:
2x-5 = x^2-8x+16
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Rearrange::
x^2 - 10x + 21 = 0
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Factor::
(x-3)(x-7) = 0
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Check for extraneous answers::
x = 3 ?
sqrt(2*3-5) = 3-4
sqrt(1) = -1 (x = 3 is extraneous)
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x = 7 ?
sqrt(2*7-5) = 7-4
sqrt(9) = 3 (x = 7 is a solution)
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Cheers,
Stan H.
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