 | Clara Avis Hart, Daniel D. Feldman - Geometry - 1912 - 504 pages
...400. If four numbers are in proportion, they are in proportion by composition and division; that is, the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. Given a : b = c : d. To prove a+ b:a — b — c + d:c — d. 1 2. 3.... | |
 | Webster Wells, Walter Wilson Hart - Algebra - 1912 - 504 pages
...equation. 313. In any proportion, the terms are in proportion by Composition and Division ; that is, the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. If 2=« prove о da — b c—d PROOF. 1. Since ?= -.then £+-*=U2. (Composition)... | |
 | Walter Burton Ford, Earle Raymond Hedrick - Geometry, Modern - 1913 - 272 pages
...If four quantities are in proportion, they are in proportion by composition and division; that is, the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. Given a/b = c/d, to prove that (a + b)/(a — 6) = (c+d)/(c— d). Proof.... | |
 | Arthur Schultze, Frank Louis Sevenoak - Geometry - 1913 - 490 pages
...THEOREM 285. If four quantities are in proportion, they are in proportion by composition and division, ie the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. Given a : b = c : d. To prove a + 6:a — b = c+d:c — d. Proof. a :... | |
 | Walter Burton Ford, Charles Ammerman - Geometry, Plane - 1913 - 378 pages
...If four quantities are in proportion, they are in proportion by composition and division ; that is, the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. Given a/b = c/d, to prove that (a + 6)/(« - 6) = (c+d)/(c- d). Proof.... | |
 | Arthur Schultze, Frank Louis Sevenoak - Geometry, Plane - 1913 - 328 pages
...THEOREM 285. If four quantities are in proportion, they are in proportion by composition and division, ie the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. Given a:b = c:d. To prove a + b : a — b = c +d :c — d. Proof. a :... | |
 | Webster Wells - 1913 - 366 pages
...proportion, the terms are in proportion bу Composition and Division ; that is, the sum of the first tivo terms is to their difference as the sum of the last two terms is to their difference. If 2 = 2, prove b d'1 ab cd PROOF. 1. Since ?=-, then 1+-^ = 1U?. (Composition)... | |
 | Claude Irwin Palmer, Daniel Pomeroy Taylor - Geometry, Plane - 1915 - 296 pages
...a proportion, they are in proportion by addition and subtraction; that is, the sum of the first two is to their difference as the sum of the last two is to their difference. _. ac Given =- = -. od — a+b To prove a—b c—d Proof. ^ = ^. od * I a—b C~d 5 -irvT And -j-... | |
 | Elmer Adelbert Lyman, Albertus Darnell - Algebra - 1917 - 520 pages
...VIII. If four numbers are in proportion, they are in proportion by composition and division ; that is, the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. PROOF. Let-=-- bd ,.^±a=c-±a. (why?) Also i^- = ^^ • (Why ?) Dividing... | |
 | Arthur Schultze, Frank Louis Sevenoak - Geometry - 1918 - 486 pages
...THEOREM 285. If four quantities are in proportion, they are in proportion by composition and division, ie the sum of the first two terms is to their difference as the sum of the last two terms is to their difference. Given a : b = c : d. To prove a + b: a — b = c +d :c — d. Proof.... | |
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Likewise, the sum of the first two terms is to their difference, as the sum of the last two is to their difference. 
