Answer:
The horizontal distance until the plane flies over the island is 2687ft
Step-by-step explanation:
An illustrative diagram of the scenario is shown in the attachment below.
P is the position of the plane, I indicates the position of the island and G is point on the ground such that /PG/ is perpendicular to the ground.
From the diagram, the horizontal distance from the plane to the island is x.
x = /IG/
In the diagram, consider triangle PIG which is a right angle triangle.
/PI/ is the hypotenuse
/IG/ is the opposite
and /GP/ is the adjacent.
From the formula,
[tex]tan\theta = \frac{opposite}{adjacent}\\[/tex]
∴ [tex]tan\theta = \frac{/IG/}{/GP/}\\[/tex]
[tex]tan\theta = \frac{x}{/GP/}\\[/tex]
∴ [tex]x = /GP/ tan\theta[/tex]
From the diagram
/GP/ = 7000 ft and [tex]\theta = 21[/tex]
∴ [tex]x = 7000 \times tan21\\[/tex]
[tex]x = 2687.05 ft[/tex]
[tex]x[/tex] ≅ 2687 ft
Hence, the horizontal distance until the plane flies over the island is 2687ft