find the value of $sqrt3{-216}$.

Explanation:

Step1: Recall cube - root definition

We need to find a number $x$ such that $x^3=-216$.

Step2: Factorize - 216

We know that $216 = 6\times6\times6$, so $-216=(-6)\times(-6)\times(-6)$.

Answer:

$-6$