Find the required variable for the frame below:

$L1=3\mathrm{.}5m$

$L2=0\mathrm{.}75m$

$L3=3\mathrm{.}0m$

$L4=5\mathrm{.}0m$

$P=14kN$

Find: Bx $($horizontal pin reaction at B$)$ in kN