If the volume of a cube is 729 m³, then the side length of a cube is ____.

Given, the volume of a cube = 729 cm³

We know that the volume of a cube = s³ (Where 's' is the side length of a cube).

The side length of a cube can be found by taking the cube root of its volume.

The side length of a cube = $\sqrt[3]{\mathrm{volume} \mathrm{of} \mathrm{the} \mathrm{cube}}$

$=\sqrt[3]{729}=9$

Therefore, the side length of a cube is 9 cm.