SOLUTION: Solve {{{ x+3sqrt(x)-40=0 }}}

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Question 367307: Solve
+x%2B3sqrt%28x%29-40=0+
Found 2 solutions by edjones, robertb:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
x+3sqrt(x)-40=0
3sqrt(x)=40-x
9x=x^2-80x+1600 square each side.
x^2-89x+1600=0
(x-25)(x-64)=0
x=25 the only answer.
.
Ed

Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
+x%2B3sqrt%28x%29-40=0+,
%28sqrt%28x%29-5%29%28sqrt%28x%29%2B8%29+=+0.
Hence sqrt%28x%29+=+5, or sqrt%28x%29+=+-8.
The second equation has no solution (extraneous solution!), while the first gives x = 25. This also satisfies the original equation, so this is the final answer.