Answer: [tex]\frac{x^{20}}{y^{15}}[/tex]
This is the same as writing (x^20)/(y^15)
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Work Shown:
[tex]\left(x^{-4}y^3\right)^{-5}\\\\\left(x^{-4}\right)^{-5}*\left(y^3\right)^{-5}\\\\x^{-4*(-5)}y^{3*(-5)}\\\\x^{20}y^{-15}\\\\\frac{x^{20}}{y^{15}}[/tex]
In the second step, I used the rule that (a*b)^c = (a^c)*(b^c)
In step 3, I used the rule (a^b)^c = a^(b*c)
In the last step, I used the rule a^(-b) = 1/(a^b)