Answer
$256$
Work Step by Step
With $b=-32$, complete the square by adding $\left(\frac{b}{2}\right)^2$:
$\left(\dfrac{b}{2}\right)^2=\left(\dfrac{-32}{2}\right)^2=(-16)^2=256$
Therefore, to complete the square, add $256$ to the given expression.
