Question 1150839
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Answer: <font color=red size=4>11.3 miles</font>
This answer is approximate and rounded to 1 decimal place.


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Explanation:


Diagram
<img src = "https://i.imgur.com/GR51iwH.png">
The plane starts at point A, then it moves 4 miles to get to point B. Point C is the end of the runway location. Angles of depression are formed by starting off looking directly horizontally, then looking down at the target. 


Segments
c = AB = 4
a = BC = x
lower case letters used for side lengths; upper case used for angles (note how lowercase 'a' is opposite uppercase 'A', same for B and C as well)
We don't need to find the length of segment b though it would be good practice for you to do later.


Angles
A = 47 degrees
B = 118 degrees (118 + 62 = 180)
C = 15 degrees (solve 47+118+y = 180 for y)


Law of Sines
sin(A)/a = sin(C)/c
sin(47)/x = sin(15)/4
sin(47)*4 = x*sin(15)
4*sin(47) = x*sin(15)
x*sin(15) = 4*sin(47)
x = 4*sin(47)/sin(15)
x = 11.302934856737
x = 11.3


The distance from point B to point C is roughly <font color=red size=4>11.3 miles</font>
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