I believe i know the answer this this one, but i just want to make sure.

Could someone tell me the answer to the following:

Factor the difference of two sqaures,

25 - (z+5)²

Also, this one, i am having a hard time finding the answer to:

Completely factor the expression,

5(3-4x)² - 8(3-4x)(5x-1)

Thanks :)