## Intermediate Algebra for College Students (7th Edition)

$-|x-5|$
The square of a binomial sum is: $(A-B)^2=A^2-2AB+B^2$. $\sqrt[n] {a^n}=|a|$ if $n$ is even. Hence here: $-\sqrt{x^2-10x+25}=-\sqrt{(x-5)^2}=-|x-5|$