Question 414298
Note: {{{k}}} is called the constant of proportionality
{{{y = k*(1/x^3)}}}
{{{64 = k*(1/3^3)}}}
{{{64 = k*(1/27)}}}
{{{k = 27*64}}}
{{{k = 1728}}}
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{{{216 = 1728*(1/x^3)}}}
{{{x^3 = 1728/216}}}
{{{x^3 = 8}}}
{{{x = root(3,8)}}}
{{{x = 2}}}