 | Eugene Lamb Richards - Measurement - 1880 - 108 pages
...produced. CD = b sin. A. ((1) Art. 30), (Art. 46). Area = $cxCD (Ch. 5, IV.), = $ bo sin. A. Therefore, the area of a triangle is equal to one-half the product of any two adjacent sides multiplied by the sine of the included angle. Suppose c and the angles A and B are given.... | |
 | Daniel Alexander Murray - 1906 - 466 pages
...(2) A is obtuse.] area ABC (Fig. 1) = J AB • DC; = \be sin A area ABC (Fig. 2) = \AB- DC; = \ be aw (180 -A). It will be seen in Art. 45, that sin (180...contained angle. EXAMPLES. 1. Find the area of the triaugle in which two sides are 31 ft. and 23 ft. and their contained angle 67° 30'. area = 31 * 23... | |
 | International Correspondence Schools - Building - 1906 - 634 pages
...substitution of this value of h in the formula in Art. 26 gives , , , S = a be sin A In words, the area of a triangle is equal to one-half the product of any two sides and the sine of their included angle. EXAMPLE. — Two of the sides of a triangular field are 39.47 and 59.23 chains, respectively,... | |
 | Plane trigonometry - 1906 - 230 pages
...The substitution of this value of h in the formula in Art. 26 gives „ , 5 = % bcsmA In words, the area of a triangle is equal to one.half the product of any two sides and the sine of their included angle. EXAMPLE. — Two of the sides of a triangular field are 39.47 and 59.23 chains, respectively,... | |
 | Daniel Alexander Murray - Plane trigonometry - 1908 - 358 pages
...is acute, in (2) A is obtuse.] area ABC (Fig. 1) = \AB • DC; = \bc sin A. area ABC (Fig. 2) = £ AB • DC-, = \bc sin (180 — A). It will be seen...ft. and their contained angle 67° 30'. area = 31 * 23 x sin 67° 30' = 31 x 23 x .92388 2 2 2. Find area of triangle having sides 125 ft. , 80 ft. ,... | |
 | Frank Castle - Mathematics - 1908 - 616 pages
...height. As any side may be considered as the base of a triangle, the rule may be stated thus : the area of a triangle is equal to one-half the product of any side of a triangle and the length of the perpendicular let fall on that side from the opposite angle.... | |
 | Alfred Monroe Kenyon, Louis Ingold - Plane trigonometry - 1919 - 306 pages
...one of the given sides, as p upon b, then p = a sin C and by (1) A = £ b (a sin C) ; whence (2) The area of a triangle is equal to one-half the product of any two sides into the sine of their included angle. 53. Area from Three Sides. If A the three sides are given, draw... | |
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Hence, the area of a triangle is equal to one-half the product of any two sides ' and the sine of their contained angle. EXAMPLES. 1. Find the area of the triangle in which two sides are 31 ft. and 23 ft. and their contained angle 67° 30'. 