Answer
$7.9K\Omega \space or \space 5.3K\Omega $
Work Step by Step
We know that
$X_L=X_c\pm\sqrt{Z^2-R^2}$
We plug in the known values to obtain:
$X_L=6.6K\Omega\pm\sqrt{(3.5629K\Omega)^2-(3.3K\Omega)^2}$
$X_L=6.6K\Omega\pm 1.25K\Omega$
$X_L=7.9K\Omega \space or \space 5.3K\Omega $
