Find all of the square roots of the perfect square $\frac{4}{9}$ .

A) $\frac{2}{3}$
B) $\pm \frac{8}{27}$
C) $\frac{1}{2}$
D) $\pm \frac{2}{3}$
E) $\pm \frac{3}{4}$

The square root of a perfect square, in this case, $\frac{4}{9}$ , includes both the positive and negative roots because squaring either will return the original value. The square root of $\frac{4}{9}$ is $\frac{2}{3}$ , so both $\frac{2}{3}$ and $-\frac{2}{3}$ are correct, making option D the correct answer.