If f(x)=|x+8|, what is the value of f(-11)?

$f \left(- 11\right) = 3$
As $f \left(x\right) = \left\mid x + 8 \right\mid$
$f \left(- 11\right) = \left\mid \left(- 11\right) + 8 \right\mid = \left\mid - 3 \right\mid = 3$