 | Claude Irwin Palmer, Daniel Pomeroy Taylor - Geometry - 1918 - 460 pages
...hypotenuse equals the sum of the squares of the two sides. Proof. In each proportion of § 435, take the product of the means equal to the product of the extremes. Then a2 = a'c and b- = b'c. Adding, a2+62=(a'+6')c. But a'+b' = c. 439. Theorem. A perpendicular drawn... | |
 | Fletcher Durell, Elmer Ellsworth Arnold - Algebra - 1920 - 390 pages
...Solution of Proportions. Ex. 1. Find the value of x in the proportion 2x+3 : 3x-l=3x + l : 2x+l. Taking the product of the means equal to the product of the extremes Hence, x =2, - f. Ans. Ex. 2. What number added to each of the numbers 5, 8, 11, and 16 will give results... | |
 | Julius J. H. Hayn - Geometry, Plane - 1925 - 328 pages
...to the fourth. Hyp.: Given that a : b = c : d. Det.: To prove that a : c = b : d. Proof: By taking the product of the means equal to the product of the extremes, we have be = ad, or ad = be. Dividing both sides by cd. we have —; = —r. ° r — = —r • ~.... | |
 | Research & Education Association Editors, Ernest Woodward - Mathematics - 2012 - 1080 pages
...proportion AC BD CE DE to solve for BD. Substituting in values, we have (v) IR* = Ì or 3 BD 2 3 ' Setting the product of the means equal to the product of the extremes, we obtain (vi) (vii) (viii) 2 2 BD = 3 BD = 10 BD = 5 • PROBLEM 262 Line segments AC and BD intersect... | |
 | William Weller Strader, Lawrence D. Rhoads - Geometry, Plane - 1927 - 434 pages
...product of two other lines is to prove the four lines proportional as in the previous method and take the product of the means equal to the product of the extremes. Sight Exercises. Proportional Lines ^ In the following exercises, 1-6, write a proportion of the marked... | |
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It is evident that the terms of a proportion may undergo any change which will not destroy the equality of the ratios ; or which will leave the product of the means equal to the product of the extremes. 
