SOLUTION: Law of sines word problem help? Points A and B are on opposite sides of a river. To find the distance between the points, a third point C is located on the same side of the riv

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Question 866963: Law of sines word problem help?
Points A and B are on opposite sides of a river. To find the distance between the points, a third point C is located on the same side of the river as point A. The distance between A and C is 50 feet, ACB is determined to be 47° and BAC is 115°. Find the distance between A and B.
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Answer by lwsshak3(11628) About Me  (Show Source):
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Points A and B are on opposite sides of a river. To find the distance between the points, a third point C is located on the same side of the river as point A. The distance between A and C is 50 feet, ACB is determined to be 47° and BAC is 115°. Find the distance between A and B.
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Given angle at point C=47˚
Given angle at point A=115˚
So the angle across the river at point B=180-115-47=18˚
Using law of sines:
sin 18/50=sin 47/AB
AB=(sin 47/sin18)*50≈118.34
distance between A and B≈118.34 ft