Algebra and Its Use, Book I has made balance and equation its keynote. Since the equation is the basic concept of mathematics, and particularly of algebra, the authors have introduced it at the very start. Thus, the student is introduced to "algebra" immediately.
Throughout the text the first emphasis is on understanding. The "why" of each concept and operation is then followed by a complete explanation of the "how". To assure the student's understanding, explanatory material is written in terms of the vocabulary and experience of the ninth-grader.
Following explanatory material for each new concept are examples and an abundance of graded drill material. To reduce mechanical manipulation to a minimum, the drill exercises are cumulative within each chapter, so that the student must analyze each problem. Mastery Tests and, beginning with Chapter 4, Cumulative Tests at the ends of chapters allow the student to review what he has learned and to evaluate his progress.
As its title indicates, Algebra and Its Use emphasizes the practical value of algebra in the student's everyday life. Chapter introductions and illustrations and photographs throughout the book point up the many uses of algebra in numerous occupations and in daily living. The state problems incorporate situations common to ninth-graders and to adults in a variety of occupations so that the student will see the purpose of his study of algebra now and its increasing value to him in the future.