Answer
Angle PST = 80°
Explanation
Opposite angles of a parallelogram are equal.
Angle R = 130° = Angle QPS
The sum of angles on a straight line is 180°.
Angle QPS + Angle SPT = 180°
130° + Angle SPT = 180°
Angle SPT = 180° - 130° = 50°
Then, we were told that ST = SP, so, the the base angles of triangle PST are equal.
Angle SPT = Angle STP = 50°
Sum of angles in a triangle = 180°
Angle SPT + Angle STP + Angle PST = 180°
50° + 50° + Angle PST = 180°
100° + Angle PST = 180°
Angle PST = 180° - 100°
Angle PST = 80°
Hope this Helps!!!
