## Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

$\dfrac{25}{4}$
To complete the square of $x^2+bx$, we must add $(\dfrac{b}{2})^2$. We can see that $b=-5$. So, to complete the square, we must add $(\dfrac{b}{2})^2=(\dfrac{-5}{2})^2=\dfrac{25}{4}$. Therefore, the missing term in the given statement is: $\bf{\dfrac{25}{4}}$.