Chapters 1 through y present the essential material of plane geometry and can easily be covered in three-unit, one-semester course, perhaps omitting the optional trigonometry section. The additional topics in Chapters 8, 9, and 10 provide enrichment materials and enable the book to be used for a five-unit, one-semester course, or for a two-quarter course. These three chapters are sufficiently independent so that any of them can be used separately...