CK-12’s Geometry - Second Edition is a clear presentation of the essentials of geometry for the high school student. Topics include: Proofs, Triangles, Quadrilaterals, Similarity, Perimeter & Area, Volume, and Transformations. Volume 1 includes the first 6 chapters: Basics of Geometry, Reasoning and Proof, Parallel and Perpendicular Lines, Triangles and Congruence, Relationships with Triangles, and Polygons and Quadrilaterals.