Answer:
102°
Explanation:
540° ÷ 5 = 108° (sum of angles in a 5-sided figure = 540°)
360° ÷ 4 = 90° (sum of angles in a square = 360°)
180° ÷ 3 = 60° (sun of angles in a triangle = 180°)
360° - 108° - 90° - 60° = 102° (angles at a point add up to 360°)
x = 102°
(Do note that dividing the sum of angles by the number of sides is only applicable if all sides are equal.)
Hope this helps! ^^