Answer:
(x^(11/4))(y^(5/9))
Explanation:
The applicable rules of exponents are ...
(x^a)(x^b) = x^(a+b)
(x^a)/(x^b) = x^(a-b) . . . . . no surprise, since 1/x^b = x^-b
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Your expression simplifies to ...
x^((5/4) -(-5/4) -(-1/4)) · y^((1/18) -(-1/2))
= x^(5/4 +5/4 +1/4) · y^(1/18 +1/2)
= x^(11/4) · y^(1/18 +9/18)
= x^(11/4) · y^(5/9)