physics

$R_x = \Sigma F_x$

$R_x = 16 \cos 180^\circ + 50 \cos 040^\circ + 28 \cos 150^\circ$
 

$R_y = \Sigma F_y$

$R_x = 16 \sin 180^\circ + 50 \sin 040^\circ + 28 \sin 150^\circ$
 

$R = \sqrt{{R_x}^2 + {R_y}^2}$
 

Direction of resultant:
$\tan \theta_x = \dfrac{R_y}{R_x}$
 

Just follow the solution above with your calculator.