10: Geometry Last updated Save as PDF Page ID 129486 OpenStax OpenStax 10.0: Introduction 10.1: Points, Lines, and Planes 10.1.0: Exercises 10.2: Angles 10.2.0: Exercises 10.3: Triangles 10.3.0: Exercises 10.4: Polygons, Perimeter, and Circumference 10.4.0: Exercises 10.5: Tessellations 10.5.0: Exercises 10.6: Area 10.6.0: Exercises 10.7: Volume and Surface Area 10.7.0: Exercises 10.8: Right Triangle Trigonometry 10.8.0: Exercises 10.9: Chapter Summary 10.9.0: Key Terms 10.9.1: Key Concepts 10.9.2: Videos 10.9.3: Formula Review 10.9.4: Projects 10.9.5: Chapter Review 10.9.6: Chapter Test Thumbnail: 2-sphere wireframe as an orthogonal projection. (CC BY-SA 3.0; Geek3 via Wikipedia )