Find the missing exponent.

Hello!
[tex]\large\boxed{-4}[/tex]
Exponent rules state that:
[tex](x^{a})^{b} = x^{a*b}[/tex]
Therefore:
[tex](b^{2} )^{x}= b^{-8}[/tex]
We can ignore the b to solve for x. Use the exponent rule above:
2 · x = -8
2x = -8
Divide both sides by 2:
2x/2 = -8/2
x = -4.