SOLUTION: solve the equation: x - 2 sqrt of x = 8

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Question 734375: solve the equation: x - 2 sqrt of x = 8
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
solve the equation: x - 2 sqrt of x = 8
.
x+-+2sqrt%28x%29+=+8+
This is a "quadratic".
Let y+=+sqrt%28x%29
then we can rewrite the equation as:
y%5E2+-+2y+=+8
y%5E2+-+2y+-+8+=+0
%28y%2B2%29%28y-4%29+=+0
y = {-2,4}
.
but, we needed x so:
-2+=+sqrt%28x%29
4+=+x
and
4+=+sqrt%28x%29
16+=+x