 If the product of two quantities is equal to the product of two others, one pair may be made the extremes, and the other pair the means, of a proportion.  Elementary Algebra - Page 318by Frederick Howland Somerville - 1908 - 407 pagesFull view - About this book
 | Webster Wells - Geometry, Plane - 1908 - 206 pages
...THEOREM 218. (Converse of Prop. I.) If the product of two numbers is equal to the product of two others, one pair may be made the extremes, and the other pair the means, of a proportion. Given ad = be. (1) To Prove - = -. bd Proof. Dividing both members of (1) by bd, ad_bc_ £_£ bd~bd'... | |
 | Webster Wells - Geometry - 1908 - 336 pages
...THEOREM 218. (Converse of Prop. I.) If the product of two numbers is equal to the product of two others, one pair may be made the extremes, and the other pair the means, of a proportion. Given ad = be. (1) To Prove . -=^. bd Proof. Dividing both members of (1) by bd, ad_bc- a_c bd bd'... | |
 | Webster Wells - Algebra - 1908 - 456 pages
...mean. 141. (Converse of § 139.) If the product of two numbers be equal to the product of two others, one pair may be made the extremes, and the other pair the means, of a proportion. Let ad = 6e. Dividing by bd, ^í?=6çlor^ = ^. ' bd bd' Ь d In like manner, we may prove that a _... | |
 | William James Milne - Algebra - 1908 - 476 pages
...proportional to a, 6, and c. Find a fourth proportional to ^, ^, and \. 478. PRINCIPLE 3. — If the product of two numbers is equal to the product of two other numbers, one pair of them may be made the extremes and the other pair the means of a proportion. For, given ad — be.... | |
 | William James Milne - Algebra - 1908 - 480 pages
...3. — If the product of two numbers is equal to the product of two other numbers, one pair of them may be made the extremes and the other pair the means of a proportion. For, given aci = be. Dividing by Ы, Ax. 4, - = - ; that is, a:b = c: i!. By dividing both members... | |
 | Elmer Adelbert Lyman - Geometry - 1908 - 364 pages
...quantities are in proportion, the product of the means is equal to the product of the extremes. 327. If the product of two numbers is equal to the product of two other numbers, either pair may be made the means and the other pair the extremes of a proportion. 329. If four quantities... | |
 | George William Myers - Mathematics - 1909 - 394 pages
...extremes is equal to the product of the means. This is a convenient test of proportionality. 11. If the product of two numbers is equal to the product of two other numbers, either pair may be made the means and the other pair the extremes in a proportion. 12. A proportion... | |
 | James William Nicholson - Algebra - 1909 - 332 pages
...like manner, illustrate each of the following principles by one or more numerical examples. (2) If the product of two numbers is equal to the product of two other numbers, either pair may be made the means, and the other pair the extremes, of a proportion. Let mq = np. tYYl... | |
 | Arthur Schultze - Algebra - 1918 - 336 pages
...product. Let the proportion be •. a : b = b : c. Then 62 = ac._(§ 163.) Hence b .= Vac. 165. If the product of two numbers is equal to the product of two other numbers, either pair may be made the means, and the other pair the extremes, of a proportion. (Converse of §... | |
| |
