Answer: 4 feet
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Reason:
Take the cube root of 64 to get 4
[tex]\sqrt[3]{64} = \sqrt[3]{4^3} = 4[/tex]
The general rule is
[tex]\sqrt[3]{\text{x}^3} = \text{x}[/tex]
where x is any real number.
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Check:
If each side of this cube is 4 feet, then,
volume = length*width*height
volume = 4*4*4
volume = 64 cubic feet
