In parallelogram PQRS, QP is extended to point T and ST is drawn. If ST = SP and m∠R = 130°, what is m∠PST?
Answer: 80°
Step-by-step explanation:
ST = SP and m∠R = 130°
If m∠R = 130°, then,
QPS = 130° ( Opposite angles of a parallelogram are equal)
QPS + SPT = 180° (angle on a staght line)
130° + SPT = 180°
SPT = 180° - 130° = 50°
PTS = SPT = 50° (Base Angle of an isosceles triangle)
m∠PST = 180° - (50° + 50°) (sum of Angle in a triangle)
m∠PST = 80°
