Answer
$x+5+2\sqrt{x+4}$.
Work Step by Step
The given expression is
$=(\sqrt{x+4}+1)^2$
Use the special formula $(A+B)^2=A^2+2AB+B^2$.
We have $A=\sqrt{x+4}$ and $B=1$.
$=(\sqrt{x+4})^2+2(\sqrt{x+4})(1)+(1)^2$
Use product rule.
$=x+4+2\sqrt{x+4}+1$
Simplify.
$=x+5+2\sqrt{x+4}$.
