Respuesta :

Answer:

[tex]\dfrac{1}{27}[/tex]

Step-by-step explanation:

[tex]n^{-\frac{2}{3}}=9[/tex]

Rewrite:

[tex]\dfrac{1}{\sqrt[3]{n^2}}=9\\\\9\sqrt[3]{n^2}=1[/tex]

Cube both sides:

[tex]729n^2=1[/tex]

Divide both sides by 729:

[tex]n^2=\dfrac{1}{729}[/tex]

Take the square root of both sides:

[tex]n=\sqrt{\dfrac{1}{729}}=\dfrac{1}{27}[/tex]

Hope this helps!