SOLUTION: 3 = x-2√x

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Question 918343: 3 = x-2√x

Found 2 solutions by tommyt3rd, MathTherapy:
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
u=sqrt%28x%29

u%5E2-2u-3=0

%28u-3%29%28u%2B1%29
leads to
u=3 or u=-1
but only u=3 is viable and it leads to

x=9

Answer by MathTherapy(10549) About Me  (Show Source):
You can put this solution on YOUR website!

3 = x-2√x 
3+=+x+-+2sqrt%28x%29

3+-+x+=+-+2sqrt%28x%29 ------ Subtracting x

%283+-+x%29%5E2+=+%28-+2sqrt%28x%29%29%5E2 ------ Squaring both sides

9+-+6x+%2B+x%5E2+=+4x

x%5E2+-+6x+-+4x+%2B+9+=+0

x%5E2+-+10x+%2B+9+=+0

(x - 9)(x - 1) = 0

highlight_green%28x+=+9%29           OR         x = 1 (ignore as this is an EXTRANEOUS SOLUTION)