Answer
$x+10\sqrt{x-3}+22$
Work Step by Step
Using $(a+b)^2=a^2+2ab+b^2$, the expression $
\left( \sqrt{x-3}+5 \right)^2
$ simplifies to
\begin{array}{l}
\left( \sqrt{x-3} \right)^2+2\left( \sqrt{x-3} \right)(5)+(5)^2
\\\\=
x-3+10\sqrt{x-3}+25
\\\\=
x+10\sqrt{x-3}+22
.\end{array}
