Question

[2/3] elevado X = 8/27

Answer 1

$(\frac{2}{3})^x = \frac{8}{27}$

Perceba que:
$\frac{8}{27} = \frac{2}{3} \times\frac{2}{3}\times\frac{2}{3} = (\frac{2}{3})^3$

Logo:
$(\frac{2}{3})^x = \frac{8}{27}\\\\ (\frac{2}{3})^x = (\frac{2}{3})^3\\\\ \boxed{x = 3}$