Answer:
11.3 Km
Step-by-step explanation:
Consider the right triangle formed by AB and West.
The acute angle WAB = 270° - 250° = 20°
and West is the adjacent side of the right triangle with AB the hypotenuse
Using the cosine ratio in the right triangle, then
cos20° = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{adj}{12}[/tex]
Multiply both sides by 12
12 × cos20° = adjacent
11.2763.. = adjacent, that is
B is 11.3 Km west of A
