The horizontal distance to the airplane to the beginning of the runway is 8 mile.
What is the tangent of an angle in a right-angled triangle?
The tangent of an angle in a right-angled triangle is the ratio of the height to the base of the triangle.
Given, the height of the airplane is = 4000 feet.
The angle of depression from the airplane to the beginning of the runway is 5.4°.
Here, the airplane forms an imaginary triangle with the ground.
The height of the right-angle triangle is (h) = 4000 feet.
The angle between the airplane and the ground at the beginning of the runway.
Let, b = the horizontal distance to the airplane to the beginning of the runway.
Therefore, tan(5.4°) = ([tex]\frac{h}{b}[/tex])
⇒ [tex]\frac{4000}{b}[/tex] = 0.095
⇒ b = [tex]\frac{4000}{0.095}[/tex] feet
⇒ b = 42105.3 feet.
Therefore, the horizontal distance to the airplane to the beginning of the runway is = 42105.3 feet = 0.0001894 × 42105.3 mile = 8 mile
Learn more about a right-angled triangle here: https://brainly.com/question/27656112
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