Simplify - square root of 7/81

$- \sqrt{\frac{7}{81}}$

Rewrite $\sqrt{\frac{7}{81}}$ as $\frac{\sqrt{7}}{\sqrt{81}}$ .

$- \frac{\sqrt{7}}{\sqrt{81}}$

Simplify the denominator.

Rewrite $81$ as $9^{2}$ .

$- \frac{\sqrt{7}}{\sqrt{9^{2}}}$

Pull terms out from under the radical, assuming positive real numbers.

$- \frac{\sqrt{7}}{9}$

The result can be shown in multiple forms.

Exact Form:

$- \frac{\sqrt{7}}{9}$

Decimal Form:

$- 0.29397236 \dots$