First we switch x and y:
[tex]x\text{ = (}\frac{1}{4}y+6)^3[/tex]Then we would solve for y:
[tex]\begin{gathered} \text{cube root both sides:} \\ \sqrt[3]{x}\text{ = }\sqrt[3]{(\frac{1}{4}}y+6)^3 \\ \sqrt[3]{x}\text{ = }\frac{1}{4}y+6 \\ \end{gathered}[/tex][tex]\begin{gathered} \sqrt[3]{x}\text{ -6= }\frac{1}{4}y \\ \sqrt[3]{x}\text{ -6 = }\frac{y}{4} \\ 4(\sqrt[3]{x}\text{ -6) = y} \end{gathered}[/tex][tex]y\text{ = 4(}\sqrt[3]{x}\text{ - 6)}[/tex]