EATON'S ELEMENTARY ALGEBRA, DESIGNED FOR THE USE OF HIGH SCHOOLS AND ACADEMIES. BY WILLIAM F. BRADBURY, A. M., HOPKINS MASTER IN THE CAMBRIDGE HIGH SCHOOL; AUTHOR OF A TREATISE ON BOSTON: THOMPSON, BIGELOW, AND BROWN, ASTOR, LENOX AND DEN FOUNDATIONS. Series of Mathematics, USED WITH UNEXAMPLED SUCCESS IN THE BEST SCHOOLS AND ACADEMIES OF THE COUNTRY. EATON'S PRIMARY ARITHMETIC. EATON'S INTELLECTUAL ARITHMETIC. EATON'S COMMON SCHOOL ARITHMETIC. EATON'S HIGH SCHOOL ARITHMETIC. EATON'S ELEMENTS OF ARITHMETIC. EATON'S GRAMMAR SCHOOL ARITHMETIC. BRADBURY'S EATON'S ELEMENTARY ALGEBRA. • BRADBURY'S ELEMENTARY GEOMETRY. BRADBURY'S ELEMENTARY TRIGONOMETRY. BRADBURY'S GEOMETRY AND TRIGONOMETRY, in one volume. KEYS OF SOLUTIONS TO COMMON SCHOOL AND HIGH Entered according to Act of Congress, in the year 1868, BY WILLIAM F. BRADBURY AND JAMES H. EATON, UNIVERSITY PRESS: WELCH, BIGELOW, & Co., CAMBRIDGE. PREFACE. IT was the intention of the author of Eaton's Arithmetics to add to the series an Algebra, and he had commenced the preparation of such a work. Although its completion has devolved upon another, the author, as far as practicable in a work of this character, has followed the same general plan that has made the Arithmetics so popular, and spared no labor to adapt the book to the wants of pupils commencing this branch of mathematics. A few problems have been introduced in Section II., to awaken the pupil's interest in Algebraic operations, and thus prepare him for the more abstract principles which must be mastered before the more difficult problems can be solved. Special attention is invited to the arrangement of the equations in Elimination; to the Second Method of Completing the Square in Affected Quadratics; and to the number and variety of the examples given in the body of the work and in the closing section. The Theory of Equations, the Explanation of Negative Results, of Zero and Infinity, and of Imaginary Quantities, are omitted, as topics not appropriate to an Elementary Algebra. It may also be better for the younger pupils to |