<h3>Answer:</h3>
2.2 miles
<h3>Explanation:</h3>
The mnemonic SOH CAH TOA reminds you that
... Sin = Opposite/Hypotenuse
We are given an angle (10°) and its opposite side length (1983 ft), and we are asked to find the hypotenuse (the straight-line distance from the plane to the runway).
... sin(10°) = (1983 ft)/distance
Multiplying by distance and dividing by sin(10°), we have ...
... distance = (1983 ft)/sin(10°) ≈ 11419.6 ft
We want to express this in miles, so we have ...
... 11419.6 ft = (m mi)×(5280 ft/mi)
... (11419.6 ft)/(5280 ft/mi) = m mi ≈ 2.163 mi
Rounding to tenths, the distance is ...
2.2 miles
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<em>Comment on the question</em>
The distance from the plane to the airport is different than the horizontal distance from the airport at which the descent must start. The latter distance is the "adjacent" leg of the triangle, so must be found using the tangent function. Rounded to tenths, it is 2.1 miles.
