If 2x^-1/2=3 what is the value of x?

This can be written as:

 

$$\frac{2}{\sqrt{x}}=3$$

 

Multiply both sides by the √x and divide both side by 3:

 

$$\frac{2}{3}=\sqrt{x}$$

 

Square both sides:

$$x=\frac{4}{9}$$

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