Answer:

square both sides:

solve the roots:

take a cube root on both sides:
![\sqrt[3]{ {x}^{3} } = \sqrt[3]{216}](https://tex.z-dn.net/?f=%20%5Csqrt%5B3%5D%7B%20%7Bx%7D%5E%7B3%7D%20%7D%20%20%3D%20%20%5Csqrt%5B3%5D%7B216%7D%20)
solve the cube root:

Explanation:
The examples of matter are Solid, Liquid and gas. Matter is defined as anything that has mass and can occupy space so if something does not have mass and cannot occupy space, then its not matter.