If four quantities are in proportion, they are in proportion by composition; that is, the sum of the first two terms is to the second term as the sum of the last two terms is to the fourth term. A Text-book of Geometry - Page 130by George Albert Wentworth - 1888 - 386 pagesFull view - About this book
| Webster Wells - Geometry - 1908 - 336 pages
...Proof. From (1), ad = be. (?) Then, £ = * (?) ac PROP. V. THEOREM 221. In any proportion, the terms are **in proportion by COMPOSITION ; that is, the sum of the first two terms** is to the first term as the sum of the last two terms is to the third term. Given the proportion a... | |
| Elmer Adelbert Lyman - Geometry - 1908 - 364 pages
...quantities are in proportion, they are in proportion by composition, ie the sum of the first two terms is **to the second term as the sum of the last two terms** is to the last term. f,. ac Given : To Prove : bd a+b _c+d bd Proof: f = ^. Then |+ ! = «+!. (Why?)... | |
| George Albert Wentworth, David Eugene Smith - Geometry, Plane - 1910 - 287 pages
...= d : c, by § 257. QED PROPOSITION IV. THEOREM 267. If four quantities are in proportion, they are **in proportion by composition; that is, the sum of the first two terms** is to the second term as the sum of the last two terms is to the fourth term. or Given a : b = c :... | |
| Clara Avis Hart, Daniel D. Feldman - Geometry, Modern - 1911 - 328 pages
...in the analysis of Prop. V. PROPOSITION V. THEOREM 398. If four numbers are in proportion, they are **in proportion by composition; that is, the sum of the first two terms** is to the first (or second) term as the sum of the last two terms is to the third (or fourth) term.... | |
| Webster Wells, Walter Wilson Hart - Algebra - 1912 - 504 pages
...by oc. EXAMPLE. Since | = Д, then g should equal ^. Does it ? 311. In any proportion, the terms are **in proportion by Composition ; that is, the sum of the first two terms** is to the second as the sum of the last two terms is to the fourth. If £ =4 prove *¥ = *¥• bdbd... | |
| Webster Wells, Walter Wilson Hart - Algebra - 1912 - 344 pages
...ac. EXAMPLE. Since J = Д, then | should equal *?. Does it ? 221. In any proportion, the terms are **in proportion by Composition ; that is, the sum of the first two terms** is to the second as the sum of the last tico terms is to the fourth. If ? = £, prove a + b = c±d_... | |
| William Betz, Harrison Emmett Webb, Percey Franklyn Smith - Geometry, Plane - 1912 - 360 pages
...are in proportion, they are in proportion by addition ; that is, the sum of the first two terms is **to the second term as the sum of the last two terms** is to the fourth term. Proof. If ^ = v then ^ + 1=^ + 1. Why ? bdbd a + bc + d Then Similarly, bd a... | |
| William Betz, Harrison Emmett Webb - Geometry, Modern - 1912 - 368 pages
...are in proportion, they are in proportion by addition ; that is, the sum of the first two terms is **to the second term as the sum of the last two terms** is to the fourth term. Proof. If £ = -, then \ + \ = - + 1. Why ? Then Similarly, bdb ' d a + b _... | |
| Webster Wells, Walter Wilson Hart - Algebra - 1913 - 300 pages
...aл. EXAMPLE. Since \ = ¿¡, then | should equal *£. Does it ? 193. In any proportion, the terms are **in proportion by Composition ; that is, the sum of the first two terms** is to the second as the sum of the last two terms is to the fourth. If J=« prove *-*• bdbd SUGGESTION.... | |
| George Albert Wentworth, David Eugene Smith - Geometry - 1913 - 496 pages
...b:a = d:e, by § 25T. QED PROPOSITION IV. THEOREM 267. If four quantities are in proportion, they are **in proportion by composition; that is, the sum of the first two terms** is to the second term as the sum of the last two terms is to the fourth term. Given a: b=c:d. To prove... | |
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