How to find the angle of inclination of a line.
How to compute the angle between two vectors.
How to define alternate interior angles and their special properties.
How to define alternate exterior angles and their special properties.
How to apply the triangle angle sum theorem.
How to label an angle and how to differentiate between acute, right, obtuse, and straight angles.
How to derive the formula to find the sum of angles in any polygon.
How to define adjacent angles.
How to use the power reduction formulas to derive the half-angle formulas.
How to determine the relationship between the side inequalities and angle inequalities in a triangle.
How to use the sine and cosine addition formulas to prove the double-angle formulas.
How to define and identify vertical angles.
How to identify a segment from the vertex angle in an isosceles triangle to the opposite side.
How to derive two more cosine double-angle formulas.
How to find the angle between planes, and how to determine if two planes are parallel or perpendicular.
How to define a central angle and find the measure of its intercepted arc; how to describe the intercepted arcs of congruent chords.
How to construct the incenter using a compass and straightedge.