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Due south of the base of a 100m tall lighthouse on level ground is a point A.
The angle of elevation from point A to the top of the lighthouse is 35 degrees.
Due east of the lighthouse is another point B.
The angle of elevation from point B to the top of the lighthouse is 22 degrees.
What is the distance from point A to point B?
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The distance from the base of the lighthouse to point A horizontally in the southern direction is
= = = 142.8143 meters.
The distance from the base of the lighthouse to point B horizontally in the eastward direction is
= = = 247.5088 meters.
and are the legs of a right angled triangle.
The distance between points A and B is the hypotenuse of the right-angled triangle
with the legs and . To find the distance between A and B, apply
the Pythagorean theorem
distance from A to B = = = 285.756 meters.
Rounding to the nearest meter, we get the ANSWER: the distance from A to B is 286 meters.
Solved.