Answer:
x = 85
Step-by-step explanation:
the exterior angles of a polygon sum to 360°
note the exterior angle at P = 180° - 90° = 90°
sum the 4 exterior angles and equate to 360
x + 72 + 113 + 90 = 360
x + 275 = 360 ( subtract 275 from both sides )
x = 85
