The volume of a cube is given by the following formula:
[tex]V=s^3[/tex]Where V is the volume and s is the side length.
Given the volume, to find the side length find the cubic root of the volume:
[tex]\begin{gathered} \sqrt[3]{V}=s \\ s=\sqrt[3]{531} \\ s=8.1 \end{gathered}[/tex]The side length of the cube is 8.1 yd.