Given an angle, draw the opposite ray of one of its sides to form a linear pair. Find the measure of the angle formed by the angle bisector of the given angle and the drawn opposite ray if the measure of the given angle is: 50°, 90°, and 150°.

Let opposite ray be drawn for the base side ray of the given angle. This gives angle 180° between these two rays. Angle bisectors of the given angles 50°, 90°, and 150° make respectively half of these angles : 25°, 45° and 75° with the base ray. Then measure of the angles between the bisectors of the given angles and the drawn opposite ray are 180°-25°=155°, 180° - 45° = 135° and 180° - 75° = 105° respectively.