9th-grade math: Geometry
Chapter 1: Basics of Geometry
Chapter 2: Reasoning and Proofs
Chapter 3: Parallel and Perpendicular Lines
Chapter 4: Transformations
Chapter 5: Congruent Triangles
Chapter 6: Relationships within Triangles
Chapter 7: Quadrilaterals and Other Polygons
Chapter 8: Similarity
Chapter 9: Right Triangles and Trigonometry
Chapter 10: Circles
Chapter 11: Circumference, Area, and Volume
Chapter 12: Probability