Remember transversals? Well, what happens when one of those things intersects a pair of parallel lines? That's what we'll find out.
Geometry 4(A) distinguish between undefined terms, definitions, postulates, conjectures, and theorems
Geometry 5(A) investigate patterns to make conjectures about geometric relationships, including angles formed by parallel lines cut by a transversal, criteria required for triangle congruence, special segments of triangles, diagonals of quadrilaterals, interior and exterior angles of polygons, and special segments and angles of circles choosing from a variety of tools
Geometry 6(A) verify theorems about angles formed by the intersection of lines and line segments, including vertical angles, and angles formed by parallel lines cut by a transversal and prove equidistance between the endpoints of a segment and points on its perpendicular bisector and apply these relationships to solve problems