Polar angles are measured counterclockwise from the positive x-axis. In the north azimuth system, the azimuth of a line is the horizontal angle measured from a meridian to the line, measured in the clockwise direction from north. In the south azimuth system, the angles are measured clockwise from south. Interior Angles. The interior angles of a triangle are the angles inside the triangle. Properties of Interior Angles . The sum of the three interior angles in a triangle is always 180°. Since the interior angles add up to 180°, every angle must be less than 180°. Find missing angles inside a triangle. Example: Find the value of x in the ... An azimuth is an angular measurement in a spherical coordinate system. The vector from an observer (origin) to a point of interest is projected perpendicularly onto a reference plane; the angle between the projected vector and a reference vector on the reference plane is called the azimuth.Nov 10, 2015 · Coordinate Geometry Fundamentals 8 Traverse loop azimuth computations 1. To compute azimuths in the counterclockwise direction, add the interior angle to the back azimuth of the previous course. 2. To compute azimuths in the clockwise direction, subtract the interior angle from the back azimuth of the previous course.