The volume of a cube is 27n^27 cubic units. What is the length of one side of the cube?
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The volume of a cube (V) is given in terms of its side length (s) as
... V = s³
You have
... 27n²⁷ = s³
You may recognize that 27 = 3³, so this can be written as
[tex]3^3\cdot n^{3\cdot 9} = \left(3n^{9}\right)^{3}=s^{3}\\\\3n^{9}=s\qquad\mbox{taking cube roots}[/tex]
This result matches your second selection
... 3n⁹ units