9514 1404 393
Answer:
(25/9)x^18·y^6
Step-by-step explanation:
Maybe you want this simplified.
The appropriate rules of exponents are ...
(a^b)/(a^c) = a^(b-c)
(a^b)^c = a^(bc)
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[tex]\left(\dfrac{3x^{-3}y^4}{5x^6y^7}\right)^{-2}=\left(\dfrac{3x^{-3-6}y^{4-7}}{5}\right)^{-2}=\dfrac{3^{-2}}{5^{-2}}\cdot x^{(-2)(-9)}y^{(-2)(-3)}\\\\=\boxed{\dfrac{25}{9}x^{18}y^{6}}[/tex]