Hello, symmetry!

You need a better diagram . . .

The tallest building in the world is the Sears Tower in the city of Chicago.

If the observation tower is 1450 feet above the ground,

how far can a person see standing in the observation tower

using the fact that Earth's radius is 3960 miles? Code:

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The height of the tower is

The radius of the earth is

The distance from the top of the tower to the horizon is

and form a right angle.

From the right triangle: .

. . which simplifies to: . **[1]**

We are told that: . and

Substitute into **[1]**: .

Therefore: . miles.