The torque exerted by the display on the hinge at a particular angle is given by:

Torque = Weight x Distance from the Axis of Rotation to Center of Gravity x Cos of the Angle.

If the weight of the display is evenly distributed, the distance from the axis of rotation to the center of gravity is equal to half the length of the display. (Example shown below)

Example:
The Angle of the Display = 45°
Weight of the Display = 2 lb.
Length of the Display = 10 in.
Distance to the Center of Gravity = 5 in. (Assuming height is evenly distributed).
Hence the torque exerted by the display on the hinge at a 45° angle is:
Torque = (2 lb.)(5 in.)(Cos 45°) = 7.07 lb.in