precal
posted by devin .
to find the distance AB across a river, a distance BC= 309m is laid off on one side of the river. It is found that B= 105.4 degrees and C= 12.2 degrees. Find AB
To find the distance AB across a river, a distance BC= 309m is laid off on one side of the river. It is found that /_B= 105.4 degrees and /_C = 12.2 degrees. Find AB
If angle B is 105.4º, distance AB is not normal to the banks of the river, assuming the banks are parallel.
With the given information, distance AB may be found using the Law oof Sines. WIth /_A being 180  105.4  12.2 = 62.4º, AB/sin(12.2) = 308/sin(62.4).
Solve for AB.
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