Books Books If the product of two quantities is equal to the product of two others, the... An Elementary Geometry - Page 27
by William Frothingham Bradbury - 1872 - 110 pages ## A Treatise on Algebra

Elias Loomis - Algebra - 1846 - 376 pages
...becomes abd bed ~T ~ Т or ad = be. Thus, if 3 : 4 : : 9 : 12, then . 3 x 12 = 4 x 9. (213.) Conversely, if the product of two quantities is equal to the product of two others, the first two quantities may be made the extremes, and the other 'two the means of a proportion. Let ad... ## A Treatise on Algebra

Elias Loomis - Algebra - 1846 - 380 pages
...becomes abd bed T=T or ad — be. Thus, if 3 : 4 : : 9 : 12, then 3 x 12 = 4 x 9. (213.) Conversely, if the product of two quantities is equal to the product of two others, the first two quantities may be made the extremes, and the other two the means of a proportion. Let ad... ## An Introduction to Algebra: Being the First Part of a Course of Mathematics ...

Jeremiah Day - Algebra - 1847 - 358 pages
...means is, in both cases the same. And if na: b :: x: y, then a: b:: x : ny. 375. On the other hand, if the product of two quantities is equal to the product of two others, the four quantities will form a proportion, when they are so arranged, that those on one side of the equation... ## Elements of Algebra: Being an Abridgment of Day's Algebra, Adapted to the ...

Jeremiah Day, James Bates Thomson - Algebra - 1848 - 264 pages
...means in both cases is the same. So if na : b : : x : y, then a : b : : x : ny. 339. On the other hand, if the product of two quantities is equal to the product of two others, the four quantities will form a proportion if they are so arranged, that those on one side of the equation... ## Ray's Algebra, Part First: On the Analytic and Inductive Methods of ..., Part 1

Joseph Ray - Algebra - 1848 - 252 pages
...equul to 8X2, we infer that the proportion isfalie. .\,.t-'2l't. — PROPOSITION II. — Conversely, If the product of two quantities is equal to the product of two others, two of them may be made the means, and the other two the extremes of a proportion. Let bc=ad. Dividing... ## Elementary Algebra: Embracing the First Principles of the Science

Charles Davies - Algebra - 1848 - 300 pages
...Thus, if we have the proportion 3 : 6 : : 6 : 12, we shall also have 6x6=6a=3xl2=36. QUEST. — 155. If the product of two quantities is equal to the product of two other quantities, may the four be placed in a proportion ? How ? — 150. If three quartiues are proportional,... ## Elements of Geometry and Conic Sections

Elias Loomis - Conic sections - 1849 - 252 pages
...: B : : B : C ; then, by the proposition, I BOOK H. PROPOSITION ii. THEOREM (Converse of Prop. /.). If the product of two quantities is equal to the product of two other quantities, the first two may be made the extremes, and the other two the means of a proportion.... ## An Elementary Treatise on Algebra: Designed as First Lessons in that Science

Horatio Nelson Robinson - Algebra - 1850 - 256 pages
...first term. This is a part of the well known rule of three, in Arithmetic. PROPOSITION II. Conversely. If the product of two quantities is equal to the product of two others, then two of them may be taken for the means, and the other two for the extremes of a proportion. Let... ## Ray's Algebra, Part First: On the Analytic and Inductive Methods of ...

Joseph Ray - Algebra - 1848 - 250 pages
...equal to 8X2, we infer that the proportion is false. ART. 345. — PROPOSITION II. — Conversely, If the product of two quantities is equal to the product of two others, two of them may be made the means, and the other two the extremes of a proportion. Let bc=ad. Dividing... 