Final answer:
To simplify 9x^2y^-3, substitute the values of x and y and solve the expression.
Step-by-step explanation:
To simplify 9x2y-3 with x = 5 and y = 3, we substitute the values into the expression:
9(5)2(3)-3
Calculating the powers first, we get:
9(25)(1/27)
Multiplying the numbers together, we have:
(9)(25)(1/27) = 225/9 = 25
So, 9x2y-3, with x = 5 and y = 3, simplifies to 25.