Horizon

The top of a lighthouse is 19 m above the sea. How far away is an object which is just “on the horizon”? [Assume the earth is a sphere of radius 6378.1 km.]

Result

x =  15.6 km

Solution:

Solution in text x =

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To solve this verbal math problem are needed these knowledge from mathematics:

Pythagorean theorem is the base for the right triangle calculator. See also our trigonometric triangle calculator.

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