ELEMENTARY ALGEBRA BY D. B. HAGAR, PH. D., PRINCIPAL OF STATE NORMAL SCHOOL, SALEM, MASS. PHILADELPHIA: COWPERTHWAIT & COMPANY. GIFT OF GE ARTHUR PLIMPTON →NDARY 25, 1924 HAGAR'S MATHEMATICAL SERIES. I. PRIMARY LESSONS IN NUMBERS RETAIL PRICE. II. ELEMENTARY ARITHMETIC $.30 .50 1.00 .1.00 1.25 VI. ALGEBRAIC EXERCISES AND KEY TO ELEMENTARY ALGEBRA. (IN PRESS.) 1.25 VII. ELEMENTARY GEOMETRY. (IN PREPARATION.) A FULL UNIVERSITY COURSE. In continuation of the above series, a complete series of Higher Mathematical Text-books, designed to meet the wants of College and University Classes, is in preparation by Eminent Professors of Mathematics. Entered, according to Act of Congress, in the year 1873, by DANIEL B. HAGAR and HENRY B. MAGLATHLIN, In the Office of the Librarian of Congress, at Washington. WESTCOTT & THOMSON, Stereotypers and Electrotypers, Philada. DEACON & PETERSON, Printers, Philada. INTRODUCTION. IN this manual the author has endeavored to apply to an elementary course of Algebra the same general plan of treatment which was adopted in his Series of Arithmetics. Every important subject is approached by means of simple suggestive questions, which lead the pupil directly to the appropriate definitions of terms, and to the principles involved in the subject. This is believed to be a great improvement upon the common plan of presenting definitions dogmatically, without any preliminary consideration of the things to be defined. The plan of combining mental exercises with written work, which has proved valuable in the Arithmetics, is also an important feature of this book. Among other characteristics of the work are the early introduction of equations, and the frequent use of practical problems which are designed to interest the learner at every stage of his progress. Great care has been taken to combine clearness and conciseness of treatment with fullness of topics, so that, in a small compass, there is furnished a course of Algebra sufficiently comprehensive for Grammar-schools, High-schools and Academies. 3 |