Answer
$$3\sqrt 6$$
Work Step by Step
We can use the product rule for square roots to rewrite the radicand as a product of the greatest perfect square factor and another factor:
$$\sqrt 54 = \sqrt 9\sqrt 6$$
Because $9$ is a perfect square, we go ahead and simplify the expression by taking the square root of $9$, which is $3$:
$$3\sqrt 6$$
