Angle D of Quadrilateral is the space between two intersecting lines or surfaces at or close to the point where they meet. And is denoted by ∠D. Angle D of Quadrilateral is usually measured using the Degree for Angle. Note that the value of Angle D of Quadrilateral is always positive. Typically, the value of Angle D of Quadrilateral lies in the range from 0 to 180.