You can find the measurements of the angles of any shape with the equation 180(s-2), where s is the sides. For example, s would be 3 for a triangle, 4 for a quadrilateral, 5 for a pentagon, etc.
A quadrilateral has 4 sides
180(4-2)
180(2)
The sum of all of a quadrilateral's sides would add up to 360.
