Answer: [tex]\bold{x^{-\dfrac{2}{3}}y^4}[/tex]
Step-by-step explanation:
[tex].\quad \bigg(x^{\dfrac{1}{4}}y^{-\dfrac{2}{3}}}\bigg)^{-6}\\\\\\=x^{\bigg(\dfrac{1(-6)}{4}\bigg)}y^{\bigg(\dfrac{-2(-6)}{3}\bigg)}\\\\\\=x^{-\dfrac{2}{3}}y^4[/tex]
