How to define and label a line segment.
How to construct a perpendicular line at a point on a line.
How to mark parallel lines, how to show lines are parallel, and how to compare skew and parallel lines.
How to identify parallel lines, a line parallel to a plane, and two parallel planes.
How to take the converse of the parallel lines theorem.
How to find the shortest distance between a point and a line.
How to prove two triangles are similar using a line parallel to a base.
How to describe and label point, line, and plane. How to define coplanar and collinear.
How to prove that opposite angles in a cyclic quadrilateral are congruent; how to prove that parallel lines create congruent arcs in a circle.
How to duplicate a line segment using a compass and straightedge.
How to construct parallel lines using three different methods.
How to define and identify vertical angles.
How to define corresponding angles and their special properties.
How to identify, define, and label rays and opposite rays.
How to describe the unit circle. How to draw the unit circle and label its parts. How to strategize about finding coordinates on the unit circle.
How to define alternate interior angles and their special properties.
How to define alternate exterior angles and their special properties.
How to describe same side interior and same side exterior angles and their special properties.
How to define and construct an angle bisector.
How to define a tangent line; how to determine the angle a radius to a tangent forms.