Answer
$\dfrac{25}{4}$
Work Step by Step
RECALL:
To complete the square for $x^2+bx$, $(\frac{b}{2})^2$ must be added.
The given expression has $b=-5$.
Thus, to complete the square, add $(\frac{-5}{2})^2=\frac{25}{4}$.
Therefore, the missing expression in the given statement is:
$\dfrac{25}{4}$
