help with negative exponents?

y^-3 means -y times -y times -y you just make it negative

With negative exponents you take the expression to the power
and then take the reciprocal.

i.e.

x^ -3 = 1 / x^3.

(5x^-3y^-2/3x^2y^-3)^-2
= 1/(5x^-3y^-2/3x^2y^-3)^2
= 1/[5^2x^(-3 * 2)y^(-2 * 2)/3^2x^(2 * 2)y^(-3 * 2)]
= 1/[25x^-6y^-4/9x^4y^-6]
= 1[(9x^4/y^6)/(25/x^6y^4)]
= (9x^4/y^6)/(25/x^6y^4)
= (9x^4/y^6)(x^6y^4/25)
= 9x^10y^4/25y^6
= (9/25)(x^10)(y^4/y^6)
= (9/25)(x^10)(y^-2)
= 9x^10/25y^2

5^(-2) x^6 y^4
-----------------------
3^(-2) x^(- 4) y^(6)

9 x^(10)
------------------
25 y ²

(9/25)*x^10 y^-2