SOLUTION: what's x? (not 0) 10 square root of x = 80x

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Question 610994: what's x? (not 0)
10 square root of x = 80x

Found 2 solutions by lynnlo, ashipm01:
Answer by lynnlo(4176) About Me  (Show Source):
Answer by ashipm01(26) About Me  (Show Source):
You can put this solution on YOUR website!
The first thing you can do to solve this is to try to combine the unknown term (x in this problem) and isolate it. First of all, let's restate the problem:
+10sqrt%28x%29+=+80x+
First, both sides can be divided by 10 resulting in:
+sqrt%28x%29+=+8x+
Next, divide both sides by x:
+sqrt%28x%29%2Fx+=+8+
Now the unknown value is all on one side, but this can be simplified to make it easier to solve. First note that sqrt%28x%29+=+x%5E%281%2F2%29 and dividing two terms with the same base can be rewritten as the base raised to the difference of their powers. Simply stated: +x%5Ea+%2F+x%5Eb++=++x%5E%28a-b%29+.
So with that, the problem can be rewritten as follows:
+x%5E%281%2F2%29+%2F+x+=+8+
Which can be simplified because x is the common base between the terms on the left hand side of the equation. So the top term is raised to the 1/2 power. The bottom term is raised to the power 1. So subtracting those powers results in:
+x%5E%281%2F2+-+1%29+=+8+
Which can finally be simplified to:
+x%5E%28-1%2F2%29+=+8+
Now to rewrite is a little differently to make it even easier to solve for x, multiply both sides of the equation by +x%5E%281%2F2%29+, which results in:
+1+=+8sqrt%28x%29+
Divide both sides by 8:
+1%2F8+=+sqrt%28x%29+
Now square both sides to get the value of x:
+1%2F64+=+x+