My nephew is having trouble solving this problem:

> 
> $$(x^{10n})((x^5)(x^{-5})^n))=(x^{-10})$$
> 
> 
> 

I'm unsure as to whether or not I can "cancel out" the $x$ in the bases and rewrite everything as follows:

$$10n\*(5\*-5^n )= -10$$

I seem to remember this from my GRE practice, but I'm not entirely sure what to do with the n in the exponent and the base in this case.

Thank you!