# Whats the absolute value of abs(45)?

$\left\mid 45 \right\mid = 45$
The absolute value of any number is its (non-negative) distance from the origin (or $0$)
That is, for any Real number $a$
$\left\mid a \right\mid \left\{\begin{matrix}= a & \text{ if " & a>=0 \\ =-a & " if } & a < 0\end{matrix}\right.$